I douubt you caused any damage. Light was on such a short period of time. Do you also have a manual temp gauge? My temp light came on once and the manual gauge indicated it was hot. I backed off like you and it cooled down quickly. Mine got hot because I forgot to take it out of the economy mode while on hilly raods.
Tim & Paula - Titusville, Florida
2015 Jayco Pinnacle 36FTBS
2011 Chevy 3500 Duramax with Air Ride Hitch