Can I sue to protect myself against false allegations that were made by my previous employer?

I reported a director at my previous job for HIPPA violation, abuse of power and unfair practices. I was instructed to lie during an investigation and when I refused and told the truth the next day I was told I was being put on unpaid administrative leave the following day. I reported them to an outside state agency and never heard back from anyone. Yesterday I received a letter that the company had substantiated neglect and reported me to DDS. They stated after further review they were closing the case. As I should feel vindicated I don't because I was lied about and an investigation was obviously conducted without my knowledge and with no input from me. I feel I have been retaliated against for doing my job and I see no relevant assistance for that of an accused other than to sit and wait to see what comes next.. Can someone please tell me what I can do?