Does your friend have hep c?
Here you go, I googled the answer for you. You should probably get tested for HepC anyways, simply because you were around high risk behavior. Especially since it's still on your mind. good luck
Hepatitis C Virus (HCV)
Based on limited studies, the estimated risk for infection after a needlestick or cut exposure to HCV-infected blood is approximately 1.8%.
http://www.cdc.gov/oralhealth/infectioncontrol/faq/bloodborne_exposures.htm