That's the sort of thing I've been having recently. I 'wake up' but I'm kind of aware that I'm not really awake but it feels as if I am (hard to explain). The other night I had this and I could see a police officer in full riot gear but with a completely hidden face in my bedroom looking ready to strike me but also backing away very slowly and I sat up and was convinced it can't be real so I shut my eyes a few times and opened them and it was still there. Genuinely the most terrified I have ever been. I actually took my pillow and threw it across the room at it to see if it would go through it and it did and then it disappeared. About 4am but that was the end of sleep that night!
I've never actually seen anything, that's something I'd dread, one of the most common visual hallucinations during night terrors is meant to be an old woman, 'old hag syndrome' I think it's called. I've had the feeling of being swung around the room, my head changing shape, hearing people whispering in my ears in the most terrifying voices, loud thuds on each of the four walls recently I had one where I could hear someone running up a steel staircase outside the house, the rhythm of the clangs sounded like they were running with a real purpose. I can sometimes sense when It's going to happen before I fall sleep, my technique to prevent it is to put earphones in and have some quiet music playing really low, usually William Basinski, don't know why that works though.