My son had night terrors around that age. He did grow out of them but it was like he was a newborn again. I would even bring him into bed with me. Do you use the night time baby oragel on him? Also don't just give him tylenol or advil. Alternate between the 2. No oftener than 4 hrs. It will take a while for him to out grow it if it is night terrors. It might be a combination of them and hurting so much. I was calling his dr all the time about this and got the same thing over and over. He's just going through teething. I hope he feels better soon, and y'all get some sleep. Also is he getting in his eye teeth or first molars? Those are the worse for hurting. Try giving him a frozen washrag when he wakes up screaming. Just rub it on his gums. It will feel awesome to him and might calm him down.