Outside shower not working

[israndy]

I have a 2006 Vista Cruiser MB I just bought, everything works except when I turn on the shower under the panel on the outside I hear water flowing but nothing comes out of the shower head. The head has a button or adjustment on the back of it and pressing it seems to make no difference. A few seconds later I start hearing water flowing onto the street. Turning off the shower and going around to the door reveals water all over the floor. The fixture has four screws holding it in, but will I break the pipes if I pull it out, or is this something that I can fix easily myself. I see the outside fixture on the internet for cheap, perhaps I should just order another...?

-Randy