I had something similar happen to me this summer. My anxiety seemed to ramp up at bedtime. My heart would pound, and I felt like I was losing my breath. Eventually, I would fall asleep but not before I worried myself half to death. I wish I had an answer for you. I know getting up and then going back to bed an hour later is an inconvenience, but if it works, I think I would keep trying it. Have you tried just waiting another hour before you try to go to bed for the first time? I wonder if that would help.
Keeping you in my thoughts and hoping you get some well-deserved rest.
April, Insomnia.Sleep-Disorders.net, Moderator