I had around 9 beers. My thoughts were, if you do it once a year surely you can control it for just your birthday, while I sat at the bar at the end of the night, i thought to myself, "Was it worth it? You know how you'll feel tomorrow right?"
Safe to say I was in a bummed out mood and everyone noticed towards the end of the night. Chugged a few glasses of water and went to bed.