Can my gf be pregnent? Safe. is this ok.

Hi there; My girlfriend and i was playing a role on 17th of February. i just inserted my penise by fault..to be at safe side i gave her ipill with in 3 hours.. after 4 hours she vomited. And at 22nd of february she got her period one day before She used to be and period was lasted for 5 day in case of 4 days. And 2nd period was late on 28th of march on place of 23 or 24. She was having white discharge before her period.. after her period end she started doing vomiting and had bleeding also dark black or brown type one day after her period... is she safe..? She got her 3rd period on 28 april and lasted for 3 days only..she daily get white discharge... i took urine pregnancy test on 26th of march and 2nd test on 6th April and both test were negative .. is this ok..? Can she be pregnent..?