I drove my CTD about 25 miles or so and the transmission was shifting fine. I parked and went into a store, (left the truck running) came back and backed out of my parking spot. I shifted into drive and realized the tranny was stuck in first. I checked the fluid ....it was full and nice and red . Not burnt at all. I drove to my parents' house in first gear, which is about a mile from the store. I parked and left the vehicle there for about 11hrs. Got in, started it up, and then drove home 15 miles or so and it shifted fine.

Got any ideas on what could have cause this???

 

My thought would be a linkage problem.
See if anything here will help you http://dodgeram.org/tech/repair/index.html#xmssn