I can't drink anymore

I used to drink occasionally in small amounts, mostly for the stimulating effects of alcohol that some people experience. I used to be one of those people, but now i'm not and it happened like a flipped switch.

I got a too drunk on new years, been vomiting for several hours after that and felt like shit in between separete throw ups. It went like vomit - feel like shit - feel better - vomit and so on, for 2-3 hours. Not the first time in my life when i drank to the point of throwing up, but this one was the worst of all times that i remember. After that I don't get any stimulation from alcohol and I just start getting tired after a certain amount. Also i don't have any cravings for alcohol anymore.

Discussed this with my GP, didn't have any idea what that could be, but we agreed that overall it's a good thing that I don't want to drink anymore.

Not that i need that, especially with my current stack, but it was a nice thing to have occasionally, when i just want to chill, so i'm interested in what could've caused this.