Heart palpitations lasting for hours with nausea

Prefacing this by saying that I have been to numerous doctors, had every blood test under the sun, and was supposed to wear a heart monitor (but it didn't work).

Basically, for a week over the summer, I would wake up to my heart beating at maybe 120-150bpm for 4-5 hours straight accompanied with horrible nausea and sometimes vomiting. I thought it was anxiety, so I did everything under the sun to try to stop it, but nothing worked, and I eventually just learned to wait it out.

Well, it happened again yesterday. I woke up at maybe 5 or 6 am and the same thing happened. I felt really weak and my heart was beating rapidly. I was nauseous and almost threw up while trying to eat bread to see if that would settle my stomach. Unlike over the summer, I remained weak and 'bleh' the rest of the day. I feel better today, but of course I'm anxious about this, so now my heart rate is up, but funnily enough, no nausea or weakness.

I don't want to waste a trip to the doctor because I already have a 1.5k hospital bill from the psych ward and burned through a 2k health savings account from all the other doctor's visits. Is it normal for tachycardia caused by anxiety to last that long and with intense nausea?