[my] I had weird anxiety dreams all night and I'm weirdly anxious now but I don't know what I'm actually anxious about

if I may share some Welcome to Nightvale wisdom

"The terror you feel in quiet moments is not misplaced, just mis-timed."

I gotta say...delayed reaction to stress was my first thought. I say 'delayed' but it's probably more like - you're finally processing, is my guess.

good point, that could be it