hmmm... 2 missions in 24's would be 6 sorties. You sure that you did not happen to fly two single sorties, for example in a C-47, or a A-20 in bomber scoring mode? So far I have never seen the game logging sorties I didn't fly, so that would be the easiest explanation
As for the disco... yes, that with the skin does always happen that way. And I found my tanks not being back to original fuel loadout, but had all remaining fuel suddenly distributed evenly across all fuel tanks.