You say there have been two negative home pregnancy tests. You now say that after you had sex using condoms, she had a period, and you have not had sex since then, which was early July, whether using a condom or not?
My guess is that she is not pregnant, since you guys used a condom always, and there have been two negative home tests after a missed period. Periods sometimes go absent for different reasons. Please try not stress over this, accuse her of anything, or harbor suspicions in your heart, you could lose her over this and then find out that the blood test is negative. There is ALWAYS time to figure it all out if she turns out to be pregnant.
Ok. We'll take a blood test tomorrow. But if she is pregnant can it be mines since she had a period after we had sex?
One late period or even absent period does not a pregnancy make, and pregnancy is possible even if a condom is used. I would not leap to conclusions; it will make you look small and unkind. She should either get a blood pregnancy test or determine to trust the home tests. Women can miss a period from stress, ovarian cyst activity, underweight, or a lot of other reasons than pregnancy.
i think she sud take a blood test to confirm is she pregnant or not. Good luck