I think my house is haunted.. I'm 13?

Sounds like you might have a spirit on your hands! Good thing you don't have a demon, you have a "practical joke" spirit. Then owners might have loved to joke around which might would explain the lights flickering on and off. Practical Jokers love to make their presence known. If you need to know more than there are millions of articles explaining the supernatural and telling you more about spirits that haven't quite moved on. If you want them to leave you need to tell them to politely leave (in a stern voice) and If you really wanna try and get rid of them you can buy some Sage leaves from your local Walmart and burn them in a metal bowl that usually works!! And is has been said that dogs possess the feeling to sense spirits. I wish you the best of luck with everything.!! (: