At the end of 3 day menstrution, got only minimal blood realease in 4th day but then have unprotected sex during 4th day. will get pregnant?

Hard to say...: It can be hard to tell if a woman is pregnant because some of the symptoms seen in early pregnancy can also happen in non-pregnant women. If worried about pregnancy, a urine test gives a reliable result.. One can test about 3 weeks after sex (3 weeks after when conception might have occurred), or 1 week after missing a period. An Ob-Gyn doctor can evaluate any unusual or worrisome symptoms.