<s>[INST] Why do I have a weird fluttering feeling in my chest as if my heart is beating fast. I feel no pain, heart beat and pressure is always normal when this happens. Only happens if I did not get enough sleep or have had a few drinks the night before, and last for a couple of hours. [/INST] If you have had the symptoms evaluated and found no underlying heart disease or dangerous rhythm, the primary concern is to relieve your symptoms and anxiety. Finding that your heartbeat and blood pressure are normal does not necessarily mean that heart rhythm is not the source of what you feel. If you can't avoid the sleepless nights and few Chat Doctor.  If you can fix the sleep and skip the booze, do that. </s>