Water pressure gone

[Retired Phil]

Took out the beast this past weekend..everything was going fine until shower time. My dw had just finished her shower and it was my turn. Halfway through my shower (pre soap/shower rinse) the water suddenly loses pressure!! I had no water coming out of the shower head. We checked the sink, no water coming out, we checked the fresh water tank it was still about halfway full!! Arrrrgh!! Has this happened to anyone else? Also is it rude to run your furnace through the night time? It gives out a little humming noise and I was wondering if that would be considered bad camping etiquette.

Phil