Well, I’m not a guy, but I can somewhat sympathize with you.
I basically have your problem, but opposite. I’m a teenage girl that’s too tall and too big (thunder thighs) for teen clothes, so I have to shop in women’s, sometimes. Now, I know that I can grow out of it, which might not help, but I’ve learned to accept it. It’s just something you’ll have to get used to and deal with. The best solution in your situation is to build muscle. Eat plenty of protein and allow yourself to bulk up. Look at Kevin Hart, he’s only 5 feet tall. I’m taller than him and i’m not even done growing…but hey, you’ll be fine man. Never be embarrassed about where you shop, as long as you look good doing it.
That probably sounds shallow, but just bulk up, okay?