The problem with most 30 something Class C's is that they lack sufficient payload. A band aid solution for you is to dump half, or more, of your fresh water tank and that gets you back to the number but does nothing for all of the additional gear you have yet to load.
What are the GVWR/payload numbers for your rig? You did not quote the front axle weights but it sounds like you were well over your GVWR of 14,500. If available you may benefit from a four corner weighing enabling you to more efficiently distribute your load. You should {IMHO}, be concerned and hopefully can find ways to reduce your weight.
Slides and leveling systems are two of the biggest consumers/wastes of your meager payload but there isn't much you can do about them. Learn to to start leaving more gear home and load the heavy stuff as far forward as possible {which can be difficult with a Class C}. Be sure your tires are inflated sufficiently for the load they carry.
Good luck!
:C