Possible trans problem

[2005powerstroke]

I was driving my 2005 foot to the floor and had to let out of it due to traffic. Traffic was going 50+ when I got back in to it. But when I hit the go pedal and nothing happened no GO i let it come back to idle while rolling and then hit the go pedal and it goes. My truck has never done this before. No major mods except exhaust and edge programer in tow tune. Please help getting ready to go to Kentucky next week.