Money lending Interest rates

While I was in college, I once got into cricket betting. I lost some money. The friend who introduced me to it , offered me friendly loan. Then, after depressing two years of my life I realized that I was ruining my life. So I gave up. But at that time I owed my Friend around 1.5 lacs. From then he became very obnoxious over course of time as I was not able to pay him the wholesome in one go. Thus to assure him I wrote a note that I owe him money and will pay back with interest. Tha rate of interest too was around 60% p.a . He didn't asked me to write a promissory note but he made me do so by regularly denigrating me. It's been 4 year now. We still are friends . I have given him around 50 thousand rupees in installments . Today I am in good government job at inspector pay grade and soon can be in civil services. It haunts me sometime that my childish mistake can cost me dearly in future. I was above 18 years at that time but certainly I was not in a healthy state of mind. Please enlighten me about this case. Ifhe files a suit in future would I be liable to pay him the whole money with the interest rate declared in the note.