I experience skipping a heartbeat that comes and goes for over a month. it mostly happens at night. what should i do? does it something to do with my heart? although my 2d echo and ekg results last june are both normal?

These are so common that they can almost be considered normal. The best way to see what is going on is to have a HOLTER for several days. the normal echo and EKg are reassuring. I would keep diary to see if you can identify food or drink that may bring them on. Especially anything that contains caffeine.

Skipped heart beat is common and you are more aware of it at night time when you are less affected by the environment. Most of the time this condition is benign and caffeine contained drink may exacerbate it. I see that you already had the work up done with EKG and Echo. To complete the work up, a thyroid function test should be considered if not done yet.