Hi! Thanks for sharing. If this is something related to your heart I think its worth visiting your doctor. I had some heart racing (tachycardia) experiences and I ran so fast to the Emergency room because its something that can be seen on monitors and can be treated. This vibration is more objective from my own experience so I think its hard for healthcare providers to understand what we have been experiencing. I hope you feel better! And if the heart racing happens again please seek help although your saying by you reducing your caffeine intake it’s gotten better. Caffeine can definitely be a culprit for tachycardia. Keep us posted!