This is not a parenting question. I am well old enough to not do this. It has only happened three times in my life. Once when I was 3 and once when I was 15. Now I am older and it happened again. I had a long dream that was verging on a nightmare, then I felt an urge to go pee, so somehow I found my parents friends old house and asked them to use the washroom. I started and when I looked down I started to feel it really happening then I flashed awake in a sweat. The night before I had had a really terrible day, which ended with some sad events.
So what does it mean when you wet the bed beyond infanthood?

It appears you did it in your dream, and most likely just that a dream. Other than that, it can be a medical issue. One time, I really would not worry about it, after that check with your doctor for medical problems

I'm with Fr Chuck... it might be a medical issue... so talk with your doctor about it.

Usually as an adult the subconcious control to NOT urinate in your sleep is so strong many people find it difficult if not impossible to urinate in one of those portable urinals when you are in a hospital bed. The dream is likely related in a subconcious way... but more of a result off rather than the cause of.

Often when reality and dreams happen simultaneously it is like lucid dreaming and you can not tell the dream from being awake. Like hearing your alarm clock go off and then dreaming you got up and got dressed. So subconsciously you most likely dreamt you HAD gone to the bathroom.

Perhaps you had to go to the bathroom very badly and your dream was indicating that to you. Then, you started dreaming of using the bathroom and that allowed it to happen.