My girlfriend wants crazy, spontaneous sex, but I lack the confidence

I'm in a relationship with a nice young lady who I constantly think about. I'm not attracted all that much to anyone but her. She's very experienced and I'm not at all. She just told me that when it comes to sex, she doesn't really want to "make love" she wants to all out f**k. She wants it rough and spontaneous. I'm not all that manly or dominant, I'm slightly overweight and pretty weak so this really scares me. We had sex once but she was only half into it, I couldn't go hard since she's loud and people were sleeping. I am a bit anti social so constant eye contact and really expressing myself would be difficult in lights on spontaneous sex. This is giving me mad anxiety because I feel like I can't offer what she wants, it's driving me crazy. And the icing on the cake, she's experienced so she has people to compare me too and will, whether she wants to or not, constantly be judging me. I'm just wondering if this is the kind of thing I can train myself to do or if you can give me any other advice. I plan on losing weight then trying to gain some muscle because I'd like to be able to do the whole pick her up, throw her on the bed kind of thing. Is it all about practice or am I just a different kind of lover that is not compatible? Any advice is wanted, I'm really losing it. Let me mention, I'm not really after a certain kind of sex, if I could do what she wanted then I would get full satisfaction.

Well the one thing you have to look at is shes already interested in you! SO she likes you already!!!!!! Don't sweat the small stuff. Actually this is a good problem to have. If shes loud you cover her mouth! Thats her problem if she loud not yours lol. Shes begging you to be slightly forceful that means dont ask for sex. TAKE IT. period. Well I mean not like some rape type lol. But walk in the house and rip her clothes of right away! Your welcome!

That's a good point... But at the same time, I know it will be hard for me at least at first. I'm just scared I'll do something goofy. Like try to take her pants off and get them stuck. Also not comfortable naked in the light yet, but I'm working on that lol I just wish my testosterone showed a little more. Thank you.