Ghostly encounters?

Hello, I have a 2 year old son and I think he may be seeing a ghost or something along those lines. We have had a dresser fall over when no one was home and an apple fall off the table as well as heard many slams and footsteps ( we live in a condo with renters on both sides, so we don't much about the noises) about a week ago he hated sleeping in his own room and woke up terrified and would run out of his room. At first I thought it was just night terrors or a bad dream so he slept in my bed. After maybe 2 days of this weird behaviour it stopped and he wasn't afraid to go into his room anymore until last night. While I was out for supper with a friend my boyfriend said they were playing and my son stopped and starred up at a spot in the ceiling and started to shake and cry, his dad asked what was there and he said "ghost"(he has never said that word before nor did we know he even knew what that was) he then hid his face in his daddies lap. A couple of minutes passed and he went back to playing normally. Later that night he went to sleep in his room with no problems, but maybe an hour into his sleep he woke up crying (as he usually does) and when he was about back asleep he looked around horrified and started shaking and crying again (this time I witnessed it) I tried to calm him down how I normally do and nothing helped, he ran out of his room and straight into our room where he hid his face and cried. At that point I was a little weirded out so we went downstairs and played and he calmed down. We took him up to sleep in our bed and he fell asleep again with no problem and around 11pm he woke up screaming and scared again (this time I thought it was a night terror ) and I said " what's wrong? is someone there" he responded " yes" and I asked " is it the ghost" and he hid is head and shook. I got him to tell whatever was in the room to leave and maybe 1 minute later my son calmed down and we watched tv for 30 minutes and he fell asleep... nothing else happened that night(last night). Do you think there is something other than night terrors going on? I am concerned because of how scared he gets. We've been living in this place for a year now with no complaints or concerns until now....