She had her period couple weeks later in June right on time but I'm scared it was just implantation

I don't know if I'm just being paranoid but my girlfriend and I had sex in May and precum may have gotten into her. She had her period a couple weeks later in June right on time but I'm scared it was just implantation.. It lasted for about 6 days. Then this month I fingered her and there was white discharge on my fingers.. Later this month she complained about having to buy bigger pants sizes.. I don't know what to do.