Hilery, My constant rapid pulse(100+) was part of the reason they kept trying to say I wasn't hypo. It's a viscious circle too. When your heart is racing, it creates more anxiety and makes your heart race.
Be sure you're taking magnesium if you can. And remember the fast pulse won't hurt you on a short term basis, it just feels awful. You'll be fine. Make sure they put you on a T3/T4 drug when this is over so you won't have to wait so long for your symptoms to go away. Hugs, IWL