tow/haul light flashing,,but didnt feel any problems

This could possibly be your tranny overheating, I had a similar problem and it turned out my cooler had gotten blocked. Moved the blockage out of the way and havent seen the flashing since. The only problem when you take it in to get checked out is there is a possibilty that they wont see the code to determine what is wrong if it is not flashing when you take it in.