I can’t hold down 3 pints of cider before throwing up. it’s ruining my social life

I used to be able to drink when i was younger and get super drunk when i was around 17. I’ve just turned 20 and can’t handle 3 drinks without throwing up. i can’t even get drunk. In scotland drinking is a very popular thing, i genuinely feel like i’m missing out on life. I understand you shouldn’t be dependent on alcohol to have to fun, but seriously let’s be honest here. I’ve ruined so many chances with girls due to this, running off to bathroom and feeling rubbish all night. I went on a date and had 2 drinks and had to sneakily be sick in toilet. kept drinking after too. another
i met this amazing girl who kept wanting to have shots with me, i had one and again had to run to the toilet to be sick. she kept wanting to have a drink with me and just thought i was boring, she didn’t understand. i went to toilet and cried, i hadn’t cried in like 6 months. everyone i try to explain it to doesn’t understand. EVERYONE. My closest friends, and family. I’m going to start having a few drinks at home and figure out if anything works. i went out on my 20th birthday with all my friends and was just not speaking trying to hold in the alcohol before going outside and throwing up on my trousers (only 4 pints). can anyone relate? has anyone ever heard of anything like this? it’s not like i’m allergic as i don’t get allergic symptoms, just feel ill until vomiting. i refuse to be that sober guy on a night out. i have considered going my doctor about this but it sounds pathetic, needing help to hold your alcohol, that’s not life threatening. if anyone has any ideas in my steps going forward please share. it would mean the world to me.