I'm 15 years old, I already had a missed period last month but pregnancy test came up negative, then last weekend my boyfriend came inside of me, am I pregnant? And when can I tell if I am or not?

Okay first do not have sex yet... not unless your ready to be a mom.. I made that mistake and now a pregnancy scare. There not fun and you shouldn't risk it. And second Do NOT have unprotected sex! And the pull out method. Never works* and no you have to wait. A pregnancy test is accurate one month after the day you had sex. If the test is positive then they never lie. If the test is negative and still no period. See a doctor in case ofa false negative. Make sure not to stress out because that also delays periods

Why are you having unprotected sex? If you are not, you will be soon.

Did you use the first urine of the morning, not latter in the day, you need to use the first to be correct.