Check with your doctor, could be symptoms of sleep apnea or maybe could just be acid reflux.
Hi korpiklaani <br />
go to see a Dr. They can easily do a heart cardiograph and see if there is a problem with it. Important you rule out anything more serious than a panic attack but even that should be subject of medical advice.<br />
Best wishes<br />
go to Dr now
If it occurs precisely at that time, regularly, it might have something to do with your circadian rhythm I would guess. Such things are usually best to investigate with a doctor's help.