I have had my tubes tied and im 31. i now bleed for 3weeks out of a month. is this normal?

Hard to know: Probably not the tubal as a cause. This tyype of bleeding needs follow up. See your pcp/gyn and get checked out. You need a blood count, exam, pregnancy test and maybe other testing. This is not normal.

One time?: Could be the result of stress, if ongoing, or spotting b/w periods need evaluation especially if overweight, smoker, or diabetic.