In my house some very strange things are happening,I first started this halloween night me and my friend took a picture and in the background you can sea someone's face in my doorway. We zoomed in and it looked just like my deceased grandfather, so after that we went in my rom and started to ask question;for example, if you have a message... knock three times and we heard three knocks but its really strange.then it got a bit worse. One night I was in the bed, I heard someone walking around my room and I kept on hearing wheezing,sneezing,and coughing . Then one night I was sound asleep when all of a sudden I heard my dog choking,so I turned on the light and she had handprints on her neck from where someone was choking her. No one would believe me and that made me even more scared. The I started to see a small girl in the corner of my room from the corner of my eye. That's exactly where my dogs have started t growling. Now the same dog that was choked,bambi, is sick and biting for no reason. She has never growled at anyone. Its scaring me and my bed heater keeps on turning on high by itself and I need help I'm scared of this I know for sure this thing is demonic. How can you tell?

I would try first to just tell them they are not wanted and to leave. Sometimes that's all it takes. If that doesn't work, you could try an exorcism... contact a priest. I know it sounds strange, but it can't hurt to try. I think there are also, things that you can do on your own like burning certain herbs etc but I am no expert.