HELP! How to not throw up after taking a shot

I’ve been drinking for about two years now. I used to drink heavily every Friday and Saturday, usually around 4–6 shots a night. Back then, all I needed was a small sip of a chaser and I was fine. Fast forward to now, I can’t take a shot for the life of me. Recently, I tried a shot of vodka, and two minutes later, it came right back up. The same thing happens with any type of hard liquor.

There was one night where I drank way too much and blacked out. Apparently, I threw up the entire night, and when I woke up the next morning, even thinking about liquor made me gag badly.

I have a feeling this might be mental, connected to that bad experience, because now whenever I get ready to take a shot, I feel uneasy even before drinking it.

My question is: what’s happening, and how can I get back to taking shots normally? For reference, I’ve already tried strong chasers, mixed drinks, breathing techniques, lowering the alcohol percentage, eating before drinking, drinking on an empty stomach and none of it works. After one or two shots, I feel that uneasy feeling in my stomach, and it always ends the same way: throwing up.

I’m not looking for “just suck it up” responses. I’m genuinely looking for a solution from people who might have gone through the same thing or who know how to deal with it.