Night Terrors?

My 2 year old for the last couple of nights has been sitting up in his bed crying hysterically. He is fast asleep when he does this. We have also noticed that he is sleeping with his eyes open (which is creepy!) We close his eye lids when we check on him throughout the night. He also sits up in his bed fast asleep and doesnt move. When he crys we cant touch him or he gets worse, except we can stroke his hair. After a few heartbreaking mins we can pick him up for a cuddle and he calms down enough to go back to bed. We do not try to wake him. We know that is a massive no-no.
We are moving house at the moment and our house is almost all packed up. We have not touched his room yet. Could this be stress manifesting whilst he is in deep sleep or is this possibly night terrors? He has a doctors appointment coming up and we will be disgussing it then.
I slept walked as a kid. Dont know if that makes any difference.