Night terror or???

My 7 yr old is freaking me out. This has happened at least 4-5 times now over the last few months, twice in the last 2 days. He goes to bed fine but has 'woken up' like he is having a night terror or hallucination. He runs through the house absolutely terrified, holding his head telling me to get it out. I don't know what 'It' is. Most of the time he is awake, but seems asleep. I can have a conversation with him but he makes no sense at all. Some of the things he says are upsetting as I can't help him. One lasted for nearly an hour before I could get him back to sleep and he has no memory of it in the morning. Tonight's one he was talking in a growly voice and told me his name, his dogs name and sisters name were all totally different but knew who I was... He wasn't 100% yesterday but had no temperature. Should I be worried or is it night terrors??