why do i get “undrunk” so fast

i sober up within 30 minutes of having my last drink. its just frustrating, i could be on the verge of passing out wasted spinning out of my mind but as soon as i stop drinking i feel normal not even 45 minutes later. like obviously when its that bad its nice, but ill have a nice buzz, start eating or something and by the time im done eating (20-30 minutes) im dead sober and dont even wanna continue drinking. i am a smaller person, but i am NOT a lightweight. it takes me an obnoxious amount of drinks to even start feeling a buzz which i find very weird for someone my size but i can literally outdrink my alcoholic mother lol. jokes aside, i do have a very fast metabolism so im thinking its that? google wont tell me anything so im just curious.