I once suffered a similar problem at RAF Mountbatten, where I'd gone for a sea survival refresher course. I had travelled back from abroad so was very tired. I booked into my room (which had twin beds) at the end of the afternoon and went for an evening meal. When I returned I realised that someone else had been booked into the same room (I had been told this might be necessary when I booked in) and had put their stuff on the other bed. I later went to bed, only to vaguely become aware of someone coming into the room and getting into the other bed.
After a while, I woke up with a start, sensing someone standing right next to my bed. What was worse was that he was obviously worse for drink and he was trying to pee in the adjacent sink. My soap, flannel and toothbrush were taking a real soaking. I just said "OI!" and he jumped a foot. Next day the bar steward completely denied it.