I think we can all agree that this is a common symptom of anxiety. I know it hapens to me a lot, and very randomly...especially when I think I'm having a good day. In all honesty, I think it's because during the day our minds are so focused on doing what's around us, or being distracted, so to speak...and at night, we're kind of left to wrestle with our worst fears, or the things that bug us.
Anyway, I took to writing in a journal when I have panic attacks at night. It helps me get a visual on my problems....and to be honest, a lot of what I panic about is stuff I have been afraid of before, so it helps me see there's a pattern....making it so I don't catastrophize as much. :)