hi Rachelle
You've come to the right place. We've got lots of answers and hopefully some ideas that will help you stay more comfortable.
Yes - cooler/wet weather will make you feel worse. I felt almost normal most of the summer but as soon as the weather changed to chilly - bam!
Yes - extreme muscle tightness or spasms CAN make you feel like you are having a heart problem. {also read about trigger points & referred symptoms/pain}
I'll add more but want to get this posted while you are still online....