For the following reasons, yes.
1. Reports stated he was driving with "rolled joints" and "a large amount of Marijuana". As a fellow consumer of such things, even with a task specific jar, that stuff smells; assuming you are buying anything better than Mexican brick weed. The idea that you would drive 20 over the speed limit in a car that would have almost certainly had an odor is asking for trouble.
2. The pills are a concern obviously, but in the context of the story, 1, aren't shocking to me (professional athlete in a contact sport - he certainly isn't alone in consuming such things), and 2, pills are much easier to hide because they don't smell like you got blasted by a skunk. Far more stealthy to transport.
3. If his car didn't presumably reek of weed, I figure the chances a trooper searching his car merely because of speeding would have been less*
4. I haven't educated myself on TN laws about Rx pills, but their rules for Marijuana are hilariously draconian - anything over an ounce is punishable by 6 years in prison on the first offense. 6 years in pound me in the ass prison for a bag of weed is hilariously out of whack compared to the "danger" of the crime.
*Realizing that a black guy in America has a different experience with cops in the US than I do, in a vacuum, 20MPH over the limit doesn't typically lead to a search of the car unless something else seems off...like perhaps your car stanking. I personally got pulled over doing 84 in a 65 on 95 in Sharon. Other than the statie suffering from some of the worst Napoleon Complex I have ever seen, he didn't dig through my car.