It got really cold last night and this morning my showers cold water wasn't working every other faucet in the trailer worked fine. I didn't hear any running water or see any leaks under the trailer. What should I do

Find the shower line and carefully apply heat-a hair dryer will work. Most likely frozen.

You should make sure that the trailer skirting is sealed as tight as possible. Then place a small electric heater under the trailer, in the area of the bath, to thaw the pipes.