Sex and college

I started nursing school about a month ago and I’m constantly thinking about that. Even when I try not to, there’s just so much to think about. I’m constantly stressed out about school, which our instructors told us is normal. But since I started school I’ve had 0 sex drive and I hate it. My boyfriends a confident person but I can tell that he thinks my lack of interest in sex right now is about him and it’s not. Any advice is helpful.