chrystalandmike, I had this happen to my truck and it was the level sender in the gas tank. Not a hard fix, but I would recommend driving the truck as much as you dare to get the tank as empty as possible. The more fuel in the tank, the more of a headache it is for the back yard mechanic to do. If you are taking it to a shop, then they have a holding tank that they will pump all the gas too. My truck is on sender #4 (one is was manufactured with, replace under a recall, replaced again under recall because the one their first installed was broken out of the box, and then one that failed on me as I was driving).
I did the job by myself. Granted, I did have the help of a high lift jack. Not a hard job, just be ready to be patient.