I had unprotected sex sept 9th now its oct 17 and i still haven't had a period if pregnant when did i concieve and how many weeks could. i be?

Can do preg. test: Pregnancy is always a possibility in a woman in her fertile years. Simple urine pregnancy tests are available at any drugstore (a woman can do the test after missing a period). A woman can also go to a primary care doctor or an ob-gyn doctor for testing. If the test is positive, the woman needs to set up routine appointments with the doctor that will be providing her prenatal care.