Why do i get pain on my side that feels like i got punched and it comes and goes every other day for the last several days. in other words one day it'll be fine and the next it'll hurt for a few hours and then go away again?

There are many possibilities, depending on exactly where the pain is located. Is it usually on one side more than the other? Depending on where it is, it could be a muscle spasm-are you doing a certain activity when it comes about? If it continues, you should have it evaluated by your doctor who can ask these questions and examine the area. Good luck!