Had unprotected intercourse 2 days ago, i was on the end of my period. today had a pink clumpy discharge with an odor, what is this??

Old blood? STD?: There are many causes of abnormal vaginal discharge. Maybe just old menstrual blood. Two days is a bit soon for symptoms from a new STD like gonorrhea, chlamydia, or trichomonas, but these still might be possible, depending on your and your partner's STD risks. If it persists a couple more days, definitely get examined. See a doctor immediately if you also get fever or abdominal or pelvic pain.