I think I have a ghost in my house what should I do?

Get a professional to help he would know what to do.

Don't panic. That will only make the spirit more restless. Call in a priest or someone of that sort, and have them try and communicate with the ghost. If it's a demon, there must be a ritual done in order to rid it of the house. If it's simply a spirit who is trapped, a non- dangerous ritual will have to be done in order to help it get to Heaven. If you know it's not a demon, then you are safe. You could also try to communicate with the spirit yourself, which may be helpful. Some spirits are protectors, while others, (demons) are killers.