Hello. Thanks for writing to us at healthcaremagic Ingesting a small amount of blood is not a risk factor because STD s that are transmitted through blood e.g syphilis, HIV need to gain access directly into the blood stream to establish an infection, which cannot happen with this route. Rest of the STD s like gonorrhea, chlamydia, herpes, warts etc are not even transmitted through blood. Nevertheless, since you were unknowingly engaged in unprotected sex with a random person, which is a high risk for transmission of HIV as well as all other STD s. Surely you should get yourself tested at appropriate intervals. Screening for HIV is with an antibody based test and it can be done earliest at 1 months. The test needs to be repeated after 3 months to cover for the window period of infection. Apart from that if in case you develop any vaginal discharge, genital ulcers or erosions, warts or growth, you should immediately get it checked with a specialist. Regards Always practice safe sex with a condom!