Jokingly getting married

When I was in school, I had been in a relationship and for fun my friends wrote a nikaah naama which included all the details like my parents' name, witnesses, lawyer, molvi (my friends pretended to be one of the characters). It even included the mahr. Then a female friend asked us separately if we accept each other as wife and husband thrice and we both said qubool hai 3 times. I had taken it as a joke and ignored it but now after several years, an aalimah I know told me that the nikkah was done at that time and I should either immediately tell my parents about this so that the nikaah would complete or ask the guy for divorce or else I would be doing a major sin. I want to confirm if I did get married or not.