Hi there, thanks for asking.

It's important to avoid the risk of unintended pregnancy wherever possible. While it's good you avoided cuming inside your girlfriend's vagina, even doing that is not 100% fail-proof, so can't be relied upon. This is because you can either slip-up in the heat of the moment and cum while still inside, or because there is often a bit of pre-cum at the tip of the penis, which can have enough sperm to fertilise an egg and cause a pregnancy.

Hopefully this is just a false alarm and your girlfriend's period has shown up by now. Periods can be late for lots of reasons (worry, stress, hormones playing up, etc.). If your girlfriend's period is still late, she should have a pregnancy test. This can be a urine test, which can be bought at chemists and supermarkets, or a blood test, which can be done at a medical clinic. Tests, advice and support are available at doctor's clinics, or women's or youth health centres.

If your girlfriend is pregnant, it's better to find out sooner rather than later so you both have time to think about it and get advice. While a pregnancy may miscarry by itself, there is a big decision on what to do: whether to keep the pregnancy or terminate it, and whether to keep the baby or adopt the baby out. A pregnancy termination, if that was the decision, is easier and cheaper to do the earlier it is, and cannot be done once the pregnancy is advanced.

I guess take this as a reminder that once we're sexually active, contraception is essential if we want to reduce the risk of creating a pregnancy every time. Condoms are easy to use and give reasonable cover against pregnancy, as well as against sexually transmissible infections. The pill or other contraceptive options need to be prescribed by a nurse or doctor.

Don't take any further risks if this is a false alarm. Preventing a pregnancy that you know you're not ready for makes more sense than trying to deal with it after it's already happened. All the best.