I had unprotected sex on the 1st day of my period, but my period ended on the 2nd day. it usually lasts at least 5 days. could i be pregnant?

If miss next period,: Can do a home urine pregnancy test. Done correctly, it gives a reliable result 3 weeks after sex (3 weeks after when conception might have occurred), or 1 week after missing a menstrual period or after having a "weird" period. If done sooner, a positive result is likely real, but a negative result may be due to testing too soon, and thus lead to a repeat test.