Help!

Jubilee
Okay so my boyfriends freaking out because he thinks I'm pregnant. Only because I've been throwing up every night for the past month or so but I honestly don't think I'm pregnant, I took a test a couple weeks ago and it was negative. So is there anything else that can cause this much vomiting? I don't drink and I don't feel sick until around 10-11pm every night and only for about 20 minutes then I puke and I feel great again. I've been working out for a month now but not difficult workouts, and I still eat like crap but I'm 18. Help please 😁