Does your new camper have an electric element to the water heater? Using a hair dryer implies just having taken a shower and if so, the electric element will be on to recover the hot water. This element can draw 14 amps by itself which is almost half that available, Hair dryer on high could be nearly the same so you have very little left for anything else. If anything else is on, you likely won't trip any individual circuit in the camper, but it will be a toss-up as to whether the main 30-amp in the converter or at the power post will go first.
2015 Rockwood Signature UltraLite 8282WS Platinum, GY Marathon LRD, TST 507RV TPMS
2005 GMC 2500HD CCSB D/A, Curt E16, Prodigy P2, Garmin RV760LMT w/BC-20 b/u cam