My girlfriend and I have been having sex for more than a year now, last year she had an ovarion cyst and after her OP the docter put her on birth control to aid in treating the cyst, but just over a week ago we had sex a day after her period stopped which she only had 4days, now she has been highly emotional, sometimes she eats a lot sometimes she doesn't eat at all and she feels sick a lot.can she be pregnant or not?