@nprofile1q... yikes. That has to be tough.
My father has a bad case of PTSD and occasionally has screaming fits in his sleep. He's most sane and manageable the rest of the time.
But his sleep has always been a tenuous thing. You didn't wake him up by touch. You just talked to him from the foot of the bed. If you touched him he might grab your arm and make you regret it