Why Am I Awake????

I had such an exhausting day today - I went out on a boat/date, met a family, drank a couple beers and was out in the sun ALL DAY LONG. That being said, I should be exhausted! Well, I am exhausted...so I went to bed early, around 10:30 pm. Why am I suddenly wide awake at 2:30 am? I thought it was because I was hungry...so I made myself a taco but that didn't seem to fix the problem. Either problem. I'm still hungry and I'm still wide awake. I'm not used to being up these crazy hours!!