Deear Erawan,
Yes, I think you do need further evaluation. It is hard to tell what type of palpitations you are having without an EKG tracing at the time. There are many different types of palpitations you could be having and the treatment would be different depending on what is happening. I would recommend asking your doctor about getting an "event recorder". This is a small EKG unit you wear around your neck. When you have an episode you push a button and it records the heartbeat. Once a diagnosis is made the best treatment can be determined. Your doctor may also consider checking a stress test to see if the palpitations can be reproduced.
I am a 39 year old male. I have always been active. A few years ago I developed an SVT and underwent 3 attempts at catheter ablation , but they failed. I currently take 300 mg of Rythmol 2 times a day. I went to the doc about 2 weeks ago because I noticed if I am doing something paticularly strenuous (example- digging fence post holes), especially a jarring motion, I might feel a palp and I get a slight pain in my chest.
If I rest it goes away and I can continue. My heart doc didn't think it necessary but let me take a stress test with the radioactive stuff and everything. My doc has not got back with me yet, but the tech who gave me the test, said, 4 minutes into the 11 minute test I showed a left bundle branch block. This lady has me scared to death. I was never told about an LBBB during all of my SVT experiences. I don't know if this is serious. Maybe this is similar to your situation. I don't know. I can relate to your troubles. Hang in there.
There's nothing like an event monitor to give you peace of mind. Any symptoms you are uncomfortable with you can record (your ekg). I am currently wearing one, it looks just like a pager, many have thought that is what it was.