I would not continue to tow either the truck or the trailer. However I would for sure weigh the truck. You may well find it weighs more than you think. The weights of many (most or all--??) Are based on the standard vehicle with out any options that are on/with the vehicle. Assume the truck is a 4x4, may have skid plates, it's own hitch, etc. These things may not be included. Also I am aware of folks that exceeded limits and were fine for awhile but eventually hitches cracked and other anomalies occurred because they were over stressed. I would not tow as you are.