I have been having problems with my heart rate lately. When my symptoms are really strong my heart rate seems to be more normal, yet even when I exercise during these times my heart still feels like it is pounding hard in my chest. I have been having periods lately where my symptoms are not bad at all and I can read, drive, be in crowds, etc. without much problem (I actually feel good!), but my heart rate and the pounding sensation I get in my chest and some veins is really high. Usually my resting heart rate is 48-54 bpm, but during these times it's 60-70. I will also go through brief moments where my heart rate suddenly drops, but the pounding sensation increases. It makes it extremely hard to fall asleep and settle down. Had anyone had problems similar to this before, and if so what helped? I have done deep breathing and have been trying to exercise as much as possible, but they don't really seem to help.