Not able to process alcohol anymore randomly.

Hello everyone. For reference I’m a male 21 and have not had problems holding down alcohol before. Recently I’ve noticed even 1 shot makes me sick and causes me to throw up. I’ve always been able to hold my liquor quite well. Usually I stop after 5 drinks. I only drink hard alcohol because beer never sits well. I don’t drink often, maybe twice a month and in moderation because I hate hangovers. I’m gonna go to the doctor and see what’s up but thought I’d ask here to see if anyone has had similar issues. Also I don’t take any medication, just some supplements but I’ve been taking them for awhile now and haven’t had this issue before. Sorry if this is the wrong spot to post this.