My period started 3/2/14 ended 3/7/14 and had sex 3/9/14 can i get pregnant? i have a 28 day cycle and period is from 6-7 days long.

Unlikely: In general sperm can live in the vaginal tract for 5 days and if you have 28 day cycles then you ovulate on day 14. If day 1 is 3/2/14 then 3/9/14 is day 8. If you have sex that day then the sperm will be unlikely to live up until you ovulate. That being said, math is hard and i would hate to take such chances. You may have gotten lucky but if you miss a period, get tested. To be sure, get plan b.