I had sex one day before my ovulation date n put a pillow under me for 20 minutes. and i also took a prenatal pill 20 after that..can i still conceive?

Yes: The best timing of intercourse to achieve pregnancy is before an egg is passed - ie. Ovulation. It may be more accurate to use an ovulation predictor kit than to rely on your best guess based on your period dates. It is a good idea, while attempting pregnancy, to take a prenatal vitamin with folic acid. Oftentimes it takes several months of timed intercourse to become pregnant.