What does it mean if the same amount of alcohol you drink every night starts getting you way more drunk than it used to?

Yeah so basically I’ve been doing this for about like two years now. I’ve literally been drinking the same exact amount of alcohol once every single day, after determining the perfect amount that’ll get me somewhere in between buzzed and full-on stupid drunk. Thankfully my tolerance never changed and I still stick to the same amount of drinks everyday. Also have to mention that the timing of when I eat meals hasn’t changed as well.

But recently(this past week), for some damn reason my tolerance became lower??? I mean if anything it should have been going up…but nooooo…shit decided to go the other way…and now the same amount of booze as before will either get me wayyy too drunk or flat out knock me out.

Obviously I should just drink less and stop whining on reddit but I’m still really curious to know what possible reasons could have caused this when literally nothing has changed in my daily life, routine and diet(weight too).

Ps. Apologies for the wall of text ^ ^