My last period was july 3-9. i had intercourse on july 27, as of right now i have yet to get my period. could i possibly be pregnant?

Maybe. Maybe not.: A urine pregnancy test, done correctly, gives a reliable result 3 weeks after sex (3 weeks after when conception might have occurred), or 1 week after missing a 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. If a woman gets her normal regular period, then she is not pregnant, and a test is not needed.

Pregnancy possible: Ovulation (the time of the month a woman can get pregnant) is "normally" about 14 days after the first day of her period. This can vary however, in each individual, particularly if your periods are not very regular. If no contraception (condom, birth control, etc) was used, you cannot rule out pregnancy. If your period is later, worth pregnancy test.