Ford Fusion 2012 SE brake noise

I'm not sure if its correlated, but i filled my wheels up to 33 psi for the winter, and out of nowhere, my driver side rear wheel started making this clicking noise at slow speeds, and it goes away if i even lightly tap on the breaks. it also does it in reverse. i've tried to check for pebbles in dust shield, and checked if the pads were loose from the caliper. not sure where to go from here, or if its safe to drive. any help would be appreciated.