Hey! (Fellow girl here.) As someone with terrible social anxiety, who used to tremble in fear around any guy, and would only talk to girls for the longest time, I know exactly how you feel!!! Good news: I was able to overcome my fear of speaking with guys (specifically with guys I had crushes on.) It took me until this year to be able to make actual friends with guys. But before I started becoming friends with boys, a gradual process of just getting used to talking to boys had to happen. Boys never took an interest in me, but I started noticing that some boys that I would sit next to in class, or have classes with would sometimes sort of try to start conversations with me. 

 I could tell it was all just friendly, but it was still terrifying. I would try to respond with as little as possible back so that they wouldn't think I was too weird, and so that I wouldn't have to talk to them. But eventually, I started responding with a bit more. Slowly, but surely, I got used to small talk with boys and then I started realizing after talking with boys enough, that they are not this foreign species after all. Even if it feels as tho we have nothing in common, hey, we were both living breathing humans, and that's enough in common to at least start a normal conversation. 

 I am proud to say that after realizing that if you speak to boys just like you speak to your girl friends, or any other regular person you talk to daily, that I am now mainly friends with boys. I actually found I had more in common with them than with most of my girl friends anyway. It will take some time, but if you just practice talking to boys enough, you will feel more comfortable talking to your crush (or any crushes you may have.) Surprisingly, most guys tend to enjoy and appreciate having a girl as a friend. (You will often get treated like a queen around them.) 

Just start small. Maybe wait a bit to talk to your crush until you're comfortable with just speaking to any boy on a more casual level. Just say hi to a boy in one of your classes. Or strike up a conversation with a boy you don't know. It will be very nerve wracking at first, but you will get used to it I promise.  You said your crush seemed nice, so if you don't want to start with anyone else, then maybe talk to him and see if you can become friends at first. See if you have things in common, or just see if you like his personality. Don't put pressure on yourself to make things happen between the two of you either (that will only increase your anxiety when talking to him.) I hope that all goes well, and you can get through it as I did.