Any advice is so appreciated because I am having a serious problem.

I have been having sex without this issue for years, but for the last while and after a few failed attempts, I can't seem to stop throwing up during any kind of sex with a guy. I will feel aroused and get in the mood, and then something changes and I start to feel sick and air fills my stomach, I break out into a full body sweat and then cant stop myself from throwing up. It is extremely embarrassing and has happened now on a few attempts with three different men (one whom I made out with and threw up). I have tried to shake it off and keep going but it just happens again and again. I cant make it past arousal to excitement even when I know in my head that I'm excited/or have been horny and wanting it.
All I can think of that might be happening is that I. On an anti depressant, 150mgs and I also smoke weed. My best friend told me that she believes I am getting too much dopamine, but even when I dont take my anti depressant for say a day leading up to sex. I also get afraid that it will happen and that sikes me out very badly and takes me to nausea right away.
When I smoke weed and take my pill and am alone and masturbate, it doesnt happen to me.

I feel like giving up on even attempting to be intimate ever again.

Any and all advice will be greatly appreciated.
(I am sure that not smoking weed would help but im looking for more advice than just that).
Thank you❤️