I've had some tests done like ECG, 2D Echo, and a thyroid test, and they all came back normal. But still, my pulse rate sometimes jumps to like 120 or 140 and then goes back to normal after a bit. I tried beta blockers for about 4 months, but it didnt really help, so my doctor told me not to worry and said it's normal for me. I've stopped taking the meds now. Should I really not be concerned about these spikes in my pulse rate?

It sounds like you have been experiencing episodes of high pulse rate despite normal results on your ECG, 2D echo, and thyroid tests. Since beta blockers did not effectively control your pulse rate, you may benefit from a calcium channel blocker such as Amlodipine. The usual starting dose for Amlodipine is 5 mg once daily, which can be adjusted based on your response. It is important to monitor your pulse rate regularly and report any persistent high readings to your doctor.