That's happened to me before. I've had it a couple times, but I can only remember one at the moment.
In the dream I was hiding in my room from my (now ex)boyfriend, I guess because he was being creepy? I don't remember really.
Anyway, I locked the door and pushed on the door, struggling to keep him from coming in, then the lock broke, the door swung open and I screamed.
Suddenly I "woke up", and my dad was there. He said "What's wrong? You should go back to sleep, it's very late". A creepy figure appeared behind him. Then I woke up for real.