Hi there, thanks for your question. It's great that you want to find out more information on what can be a confusing situation.

It sounds like you and your boyfriend are starting to experiment sexually with each other. At 15, you are going through puberty and your hormones are racing so it's natural you may have sexual thoughts and feelings and want to experiment. However, you should only have sex when you feel ready and should never feel forced into it. If you are forced into it, this is assault and you should tell someone you trust.

Did you know that at your age, you are still under the legal age of consent for sex? (Have a look at the link below for more info.)

If you and your boyfriend are going to have sex together in the future, or do foreplay with each other, it's a good idea to get into the habit of using condoms. The more you use condoms, the more familiar they will be and the easier they will be to use. Condoms are important because when used correctly they offer you the best form of protection from sexually transmissible infections (STIs) and unwanted pregnancy.

It's true that a woman can get pregnant from pre-cum or pre-ejaculate, because it can sometimes have sperm in it. She may also get pregnant if any of the cum or semen goes just inside the vagina, or on the outer lips of the vagina, because if there is enough lubrication, this seminal fluid may find its way into the vagina, which can lead to a pregnancy. Although this situation is unlikely, it's important to know that pregnancy can happen this way.

If you are woried, you might like to talk about this with a doctor or women's health nurse, especially if you miss your next period. They can talk with you about contraception options and can do a pregnancy test if necessary.

Hopefully this helps you. Take care.