Hi new mommy welcome to the group :) I have battled anxiety for 8 years having anxiety is ok it wont hurt you its just your body working but at the wrong time but at least u know u are healthy and everything is ok my anxiety was pretty high when I was preggers but just distract yourself best advice I can give u
Definately sounds like an anxiety attack to me, i remember the first time i had one, i thought i was going to die! Heart was racing, came over all hot and shaky, and felt exhausted for the rest of the day. Worst thing is, they hit out of nowhere, totally unexpected and thats what scares you. Get a doc to check you over, maybe they can tell you some relaxing techniques in case it happens again, it will help put your mind at ease.
Your hormones are high. They're changing....it could be just part of the mood swings. If it gets too bad or if you cant handle it, talk to your dr. I'm not sure of anything else that can be done....maybe someone else will post something.