Girlfriend's period is three months late, two home tests show negative, but she's showing symptoms

Hello all,

I will try to make this short, my girlfriend and I had unprotected sex around the middle of January where I DID NOT CUM in her! However, she's been two months late and we are about to come up on month three in a week. She has taken two tests and both have shown negative, however last week she started to have stomach pains along with pregnancy symptoms, like sore breasts, frequent peeing, and nausea, which she hasn't shown before. She went to the doctor and was told she has a stomach infection, but also got blood work done to be sure.

I just want to know how likely is it that she's pregnant? She has been late three months before about 6 years ago, and her mom also has had cysts on her ovaries.

Any and all information is welcome, thanks.