Tiredness during the day and night terrors

I get up at about 5:30am and I go to bed usually at 10:30pm. But by about 4pm I'm feeling really tired and have to try and sneak a nap while at work for about 20 minutes.

Also I wake during the night and constantly think my girlfriend is in trouble and I grab her. After almost 2 years she's obvioulsly pretty annoyed everytime this happens. She snaps at me and apparently I argue with her in my sleep about the danger she is in. This used to happen every night until our daughter was born 8 months ago, and it suddenly stopped until about 3 months ago. It only really happens now and then nowadays but it's still pretty annoying. I'm not sure if my tiredness Is connected to these night terrors/dreams as like I said, it only happens now and then although I am constantly getting this tiredness. The tiredness also gets more intense towards the end of the week.
Also, not sure if this will help but my 8 month old daughter is a terrible sleeper also.
Any ideas?