Hello. Thank you for writing to us at healthcaremagic
It is really very foolish on your part to have unprotected sex, not once but twice, specially since you already knew beforehand that he possibly has multiple sexual partners and likely carries an STD's.
There is no way you can do anything now to prevent an STD if you did caught one from him.
I would suggest you to visit a sexual health specialist for
counselling regarding safe sexual practices and also to get tested for all possible STD's.
Moreover, if you develop any suggestive symptoms or signs of an STD e.g urethral or
vaginal discharge,
genital ulcer, erosion, any growth or swelling you must get yourself checked and treated appropriately.
Screening for STD's like HIV and syphilis can be done earliest at 1 month and should be repeated at 3 months for a conclusive result.
Herpes can be tested by detecting
antibodies against it earliest at 2 weeks.
I would also suggest a swab test for
gonorrhea and chlamydia at 2 weeks from your sexual activity.
Regards
Always practice safe sex with a condom!