Nauseous after Making out?

I don’t know if this is something weird or unusual or not but I just wanted to post to see if there was anything that could tell me what’s up / if there’s a way to stop it.

About a year ago was the last time I actually had a full blown make out session with someone, and I noticed that after it I would feel nauseous or want to throw up? I thought it might have been because too much spit or something like that or even the person,

However last night I (finally) got the chance to do it again, with a different person and got the same outcome. Actually this time I DID throw up, (they never found out.) and I’ve been afraid to kiss them more than just a peck since that, because it makes me feel like I want to throw up again.

I’m not sure if there’s something I’m doing or if It’s just a normal thing for some people or what. I just want to find out as much as I can