Hey Im 16 and I had sex with my boyfriend on feb 18th, the last day of my period, we used a condom but I was still worried about getting pregnant.. I had my period for this month (march) on March 14 (wed.) its now march 18th and my period is REALLY LIGHT. It looks like its going to end today. Usually my period last 6-7 days. But this time it was heave the first 2 days and now is lightening up. Do you think there's something wrong or do you think this is normal or I might be stressed out or something else.. PLEASE HELP I worry a lot and I just want to know what I should think, know, or do.
THANK YOU

This sounds rather normal. You are 16 so your periods may vary like this on occasion. And, yes, stress can cause this too.

You probably already know that there is no birth control that is 100% effective. Some condoms do have microscopic holes in them. The best protection is abstinence. However, if you find that you cannot abstain then two forms of birth control are better than one. For instance, the birth control pill along with a condom is slightly more effective than just one form of birth control.

At your age, your periods can vary in length and amount, but if you are worried, wait 1 week and test using the first urine you pass when you wake up in the morning to check and put your mind at ease, as no birth control is 100% safe.