I may not be a guy, but I can tell you that he is most definitely gay and most definitely interested in you.
100% straight guys don't do all that stuff you described. Really, they don't. They would probably rather stick their hand in hot boiling water than do that. Plus, all that wrestling sounds like incredible sexual tension to me. And how he lay on top of you and held your hand and talked to you for 10 minutes? Definite attraction! Think about it, would you do that to anyone you didn't like? More likely, would *anyone* do that to anyone they didn't like?
I say the next time you're wrestling, if you want to be bold, kiss him. I mean, it really really looks like he's obviously gay, or at least bi, and obviously into you. If that's too bold, have a one-on-one talk with him. Talk about relationships. Hint around that you might be gay or bi. (Refer to "people" instead of "girls" when talking about who you want to have relationships with, hint that you'r open to relationships with all diff. kinds of people, so on. If he's straight, I don't know if he'd actually pick up on the hints. And if he's gay, well he'll so pick up on the hints) Then when you get the sense that you've hinted enough, tell him you're attracted to him. Or sit really close to him, brush his hand, and see how he reaacts. If he doesn't move away, he's definitely into you and you can tell him. I mean, I imagine that attraction works the same whether your male, female, straight, gay, bi... if you like someone, you'll want to be near them beyond the personal bubble. If you don't, you'll move away. Doesn't matter your sexuality here.