SS question.. what should I do?

My mom went into a skilled nursing facility in Oct. for rehab. In nov, she was changed to permanent resident. I did not know this until after I had paid her bills from her SS check. I have POA on her account and have always done this for her and given her the rest of her money to do as she pleases. She doesn't get much. The NH asked me to wait until this month mid-month to notify SS on her address change because they are in the middle of an account changing system. All residents will have new accounts. So in Dec, I did the usual, took her money out and wrote a money order to the NH for the check amount minus the 50 she is allowed to keep. Her Medicaid is still pending. Will I be in trouble with SS for not being a representative payee? I am just reading about this here.... I don't know what to do... they had her sign some admission papers, I am going to check with them to see if they had her sign for them to be the payee... which I want to happen anyway... much easier for her and myself.