The "erflies" in my stomach are making me feel sick!?

I always cuddle with this guy that I’m talking to. Just like anyone else, I get erflies when he says something cute or slightly ual. I’m a senior in high school and he’s a freshman in college. I’ve never had a boyfriend or anything before so this is all new to me. When we cuddle, I always get these crazy erflies. However, sometimes the “erfly” feeling gets so intense that it makes me feel nauseous. I’m not repulsed by him at all haha so that’s not it. But I’m not sure if it’s nerves or what. The more physical we got (nothing extreme) the more I felt I was actually going to be sick. It would come and go pretty quickly, however. Why is this?! I hate it because I want to be close to him but every time we get close I start to feel sick. How can I calm these erflies down?? Is it because this is my first experience? Please give your input!