Can I be charged with a crime?

After an affair with a married women ,her husband found out and demanded she file for a protection order and told her what to write . She admitted to me in text that she knew she lied and filed for a false protection order , the judge told her three times if she went ahead with it that he had to report it as perjury , she did request the order be dismissed. In the course of this affair , she bought a house and agreed to pay the bills if I said nothing , she bought me a car and gave me had written notes that are singed and dated where she states she will pay me 100,000 over time . I bought the house from her . After she filed the false documents to get a protection order ,I told that I am considering legal action against both of them , In return they have threatened to go to police and have me charged for extorsion . Not sure what to make of it , she wrote the notes ,she signed them , personally think her notes equal a contract . Yes she gave me money , I also gave her money . Can they have me charged ?? If your comments are right , why did the judge dismiss her protection with prejudice ? She admitted she was forced to do it and what to write .