@Elijah: ask and ye shall receive. I'm going to not-so-briefly change the subject back to women because I think we're fairly similar mentally and physically so perhaps you can glean something from my experience.
I was a late-bloomer with regard to puberty and physical/sexual maturation, and around that time I become more reserved, shy, and 'in my own head' for lack of a better term. I was perfectly happy in the sense I felt relatively content with life but I never could do much in the way of initiating social interactions, especially with girls/women. I didn't lose my virginity, let alone have my first kiss until about a month-and-a-half prior to my 21st birthday.
I met my only serious girlfriend via Tinder in what I would describe as a bit of a freak accident. She was looking for a committed relationship and not 'playing the field' like most Tinder-goers. We met in early November 2015, had a great conversation over the course of several hours and exchanged numbers that night. She was living a little over an hour away, going to college while I was literally living in my parents' basement investing all my time in flight simulation. She was driving to a party across the state one night and our search radii overlapped -- it was truly a statistical accident that we met. But we hit it off, texted for a couple weeks, got to know each other (during which I asked her out at some point). We finally met up, spent a day together and ended up dating for 18 months.
She was a really cool girl so I moved to go to her college. After the honeymoon period passed politics got in the way. She's catholic and conservative, I'm agnostic and progressive. Things went off the rails late-2016/early-2017 and she left me in May 2017. It was damn hard, because again, that was my first relationship + all the other 'firsts' that come with it. I still feel strongly about her in some sense. Obviously I'm less emotionally attached to her now than I was then because time causes the emotions to fade. But at a very rational level I've come to realize that she and our relationship were pretty damn good. Given that it was my first relationship I had no point of relativity to which to compare ours while I was in it, which in hindsight I wish I did.
Here was the other hard thing to mentally reconcile after that relationship: we met by accident on Tinder. What I mean by that is that I came to realize that the odds of meeting another person like her on that app was next to '0'. That meant I had to get out there and actually interact with girls in the real world in order to find another relationship like that one, something I'd never done before. That made it really hard to move forward. Since then I've slept with 7-8 different girls I've met through Tinder over the past year or so, gone on a dozen or so dates, some good, some bad, but nothing compares to that first relationship.
Here's where I'm going with this: at least in my experience, not all company is good company. Maybe I'm a bit soft in this regard and I understand that my preferences aren't reflective of everyone else's, but take your time to find the right person to invest in. I'm kind of rambling at this point but to quote the Magic Johnson meme Kontra posted, "not all ****(y) is good ****(y)". I'm not sure if my weirdly emotional essay about my one serious relationship will be helpful or relevant, and I've considered removing it from my post entirely but hopefully it will give you some food for thought.
As far as specific things to help you pursue girls: using the dating apps is fine, I still do, but make an effort to socially interact with people in the real world, men or women. Strike up a conversation, ask them a question about their day, and try to put yourself in their shoes. Imagine what you would like someone to ask you and ask others those questions. Simply make a comment on something they're wearing, compliment them. You'd be surprised (or, maybe not-so-surprised) at the reaction you'll get.
Don't be afraid to simply ask a girl out, be it through text or in person. Don't make a big deal of the situation, just ask if they want to hangout sometime, grab a coffee, or get a bite to eat. No pressure, no expectations, just see where things go. If you're feeling more ballsy, invite them over to split a bottle of wine and watch some Netflix. It may seem a bit forward but as long as you're respectful and are willing to take "no" for answer there will be no problem. The idea of being assertive and forward is not incompatible with the idea of being respectful. The only issue you'll run into here is rejection, but if you get told "no" enough times you'll become pretty numb to it. I used to have horrible rejection sensitivity and was terrified to ask a girl out ... the only way I got over it was by hearing the word "no" a hell of a lot of times. Big thing here is you have to be willing to accept "no" for an answer; don't be a piece of **** who keeps pursuing a girl after she communicates she isn't interested. You seem like a real good dude though, so I don't think you'll have any issues on that front.
Exercise and pursue hobbies. Another cliche but it's true. I know you mentioned you're short, which I am as well, but I average 190 pull-ups and 315 push-ups per week. I'm not big but I'm well put together. If you're worried about your physical stature then I'd recommend some upper body exercises. But this goes for anything: simply pursue an interest and invest time in it. It'll make you an interesting person and other people are attracted to that, especially those of the opposite sex. Don't pick something up because you think others will like it; pick something up that you're genuinely passionate about. Cultivate yourself and others will notice.
And finally I'd say attempt to accommodate for what you think are your weaknesses or deficiencies, while taking advantage of your strengths. I'm nerdy and quirky but I have a stereotypical goofy, Jewish confidence in social interactions. Be 100% genuine and authentic. If someone doesn't appreciate that, it's not your fault. Most people would rather not interact with someone who is trying to be something they are not in order to please others, rather than someone who has incompatible interests but is 100% genuine. Be the latter, not the former.
Since you're shorter maybe get a pair of boots? They'll give you an extra inch or two if that'd be appealing. Don't be arrogant but do be confident. Just know that confidence is not the same to everyone, so be your version of confident. Approach more petite girls (if that's your thing). You won't be short or small to a girl who's 5 feet tall and weighs 100 lbs, and at 5'6" you'll still be able to toss her around in bed. Learn what you like in others and seek people who embody those things.
I hope some of this has been helpful. I suspect we're not all that different and that the majority of guys out there are in the same situation as you ... hell, I sort of am, too. I also know most of this post was stuff you already know but perhaps hearing it repeated in a different way may help. If nothing else, getting a little support from fellow Pats' fans can't hurt.