Hi, Jessica, and welcome! I'm glad you found us and joined in. Many with fibro feel like they have the flu. I know I can feel hot one minute and cold the other. I don't have this all of the time, either. It comes and goes.
Do you have a doctor? I certainly wouldn't go to the emergency room for this. It doesn't sound like an emergency. But, if this has been going on, you need to talk to a doctor and they need to run some tests on you. Many of the same symptoms of fibro are like that of other illnesses so these have to be ruled out first. You do want to have the chest pain checked out...for peace of mind. It's probably nothing and could easily be from anxiety over how you are feeling right now. It's better to be safe than sorry. I developed heart palpations a few years ago and, even though these can happen with fibro, I was thoroughly checked out. It's better to be safe than sorry.
Be sure to read Fibro 101...the second thread on the forum. There are links to good info about fibro and you will learn a lot there. Good starting links are called Symptoms, What Else Could It Be, and A Thorough Explanation of Fibromyalgia. This can help you see what this illness is all about.
I'm looking forward to getting to know you better. Don't hesitate to ask questions because we are here to help you. Hope to hear more from you soon.
Sherrine