Had unprotected sex 3 days before period. is it possible to ovulate a few days before expected period, get period on time, and still become pregnant? or does having a period mean pregnancy did not occur?

Ovulation can occur outside of the typical time. If you had a full regular period, you are most probably not pregnant. To avoid stress and anxiety about this in the future, use regular contraceptives. Oral hormonal contraception is just one option. There are shots that last 3 months, implants that last 3-5 years and IUD's that can last 3, 5 or 10 years. Talk to your Dr.