ive done the same thing.....im 20 ...these things happen....im not too worried ....because its just your body needs to do something functional while its shut down....the two cross and sometimes since your mind doesnt wake up enough in time your body takes care of the function....the reason why children wet the bed are because they are still learning how to control their bladders...thats how we develop bathroom scheduales...i always go to the bathroom before sleeping and very rarely do i need to use the bathroom in the middle of the night...but if i mess up my scheduale (drink a bottle of water and dont pee before bed) then my body gets off guard and there are times where i wet the bed....