I had sex for the first time on Wednesday the 12th. It was unprotected, but he pulled out before he ejaculated. Of course, I know this isn't a 100% effective. I was planning on taking the morning after pill just in case, but I got my period today, Friday, March 14th. Is there still a chance that I may be pregnant? Should I take the pill just in case? Or should I wait a week and then take the pregnancy test?

It's still possible you might be pregnant. And remember the morning after pill has to be taken within 72 hours of intercourse and is still not guaranteed that it will abort the pregnancy.

The withdrawal method is not 100% effective, nor is it 50% effective, it's just fun sometimes.

Unfortunately you now have to wait until you are due for your next period to test. It takes a while for the pregnancy hormone to build up enough to be detected.

If you don't get your next period, then take another test, as J_9 said. If you had unprotected sex, you also need to get a full std screening done. Even if he said he didn't have any or if you didn't notice anything that looked wrong. Sometimes the person won't have symptoms but you can still contract it. With stds, it's really important to get them diagnosed and treated quickly.

Hopefully, everything is OK with your health and you aren't pregnant. But you should see a doctor just to make sure you didn't catch anything, It's better safe than sorry, especially since some stds like strains of the HPV virus can cause cancer and other health problems. While you are at the doctor's, talk about birth control options, so you don't have to worry like this again.