why is it that after staying too long in sea or pool, theres a feeling that you seems to float in water.?

Answer 1

I believe you are talking about the oppostie of 'sea legs'.

Your sense of balance is controlled by your inner ear. When you body is constantly rocking (as on a boat), your sense of balance (inner ear) is in constant motion.

When you get onto dry land, your inner ear may take a while to adjust back to the lack of constant motion. Thus your ear may be telling you that you are still in motion and affect you balance for a while.

Answer 2

ya tt's true enough. I experience that before.