I fell and hurt my lower back, if I sit or try to stand I get pain but when I stretch it seems to help the problem, could I have damage a disc in my lower back? I have had the pain for 5 days now and no amount of pain killers seem to help cure the pain.

It's very likely you pinched a nerve between two discs. Fairly common. More so than rupturing a disc. I swear by Chiropractic Doctors. A good one will take x-rays and then 'Adjust' your spine accordingly. You will still be sore for a few days due to swellin g of the inflamed tissue about the spine from the fall. But should feel some immediate reief at the adjustment.

Good Luck