Did I just buy a 5th wheel?!?!?! What did I get into?

Find out the payload of the truck like others mentioned and get a grasp on how all the weights work and how to calculate it all out. Once you have all the information and understand it you can make an informed decision on how to proceed. So many people go by the what It says I can tow and skip the other weights (I did the first go around). All the different configs per truck just make it that much more confusing. Good luck and enjoy