im trying to figure out of i can get help with money i am owed from a written and notarized contract.

I came into some money from my mothers life insurance plan at the age of 22 and was confronted by a mutual friend who informed me that he had businesses and could help with investing my money. we met at a office in white plains around October 2017 and i loaned him 40,000$ and signed a contract which stated that he had to pay me and interest of 7500 quarterly starting in January of 2018. he was late payingme the intital 7500 and had me wait till around June which was my second quarter and gave me 11k and then he started to state how he couldn't honor the contact anymore because he looked over it with his lawyers and saw it wasn't a good idea. There is a lot more information like that i felted used and its like he took advantage of the situation because i am a caring person he kept pushing me to the side when i kept asking about my money and sated that he needed my help to help him make money. . i have my copy of the contact which was singed by him and notarized.