If u want to confirm whether its black magic or not, then go for an astrologer. If the astrologer confirms u then take his advice on how to overcome this. If u cannot do that, if u r a brahmin and if u r initiated and if u know nrusimha mantra and sudarshana mantra then try to do both either combined or differently.I will give u the sankalpa which has to be done before. If u chant one lakh times the sudarshana mantra with nrusimha mantra , no black magic( even if it is of the highest form) can sustain. If u r not initiated then go to an acharya either learn it or persuade him to do it on ur behalf. I have personal experience about this mantra being successful. The least u can do is to read mantra raja pada stotram. Read it daily 108 times or 10 times in brahma muhurtha in an empty stomach and do sankalpa before reading it, if chanted for 48 days continously every prayoga would vanish out. Nrusimha mantra is the quickest remedy for this.