If your girlfriend attends a school where there is a school nurse tell her to go and talk with the nurse. She more than likely isn't pregnant if you didn't have vaginal intercourse, but she may be worried about the possibility and perhaps she is just convincing herself that she has the symptoms of pregnancy. The school nurse could give her some good advice and perhaps explain to her how to use a pregnancy test.
It is unlikely she is pregnant. She may have the flu or getting ready to start her cycle. If you know to use a condom, please do always so you do not get an STD nor need to worry about pregnancy.
The only way to know if someone is pregnant is by a pregnancy test, as symptoms are unreliable to go off of. She should probably go to the doctor to get tested for STDs, STIs, and also for pregnancy. Having sex is no small matter, so you need to be ready for the consequences of your actions. Are you ready to be a dad? If not, you probably shouldn't be having sex, and unprotected sex at that. Pre-ejaculation is the 'wetness" you have when you have an erection, and you can't even feel it when you do this. This liquid could easily seep out from having anal sex and get to her vagina. If she is late for her period, buy a home pregnancy test for her to use. Otherwise, think about whether or not you are really ready to be engaging in this type of activity.
the only way u can know for sure if she is pregnant is for her to get a pregnancy test. yall will have to tell ur parnents to buy one