I have 3 handles in my shower; hot, cold, and diverter. I replaced each of the faucets, but was unable to remove the seat screws in each, although I did try pretty hard. I am now getting mixture or hot and cold water when I turn the faucets on? Could I have damaged the seat screws and would this allow for the water to come out of the faucet mixed when only one of the hanldles is turned on? Thanks.