Period problem. Due to blood donation?

Hi. In march 4 2018 i had my period and again on 2nd april 2018 i have my period.and i had a unprotected sex with my bf on april 29th at 2.30pm but he ejacuated outside.and on 1st may 2018 due to the fear of pregnancy i had taken an Ipill i.e. to between 48 hours of intercourse and from 2nd may 2018 there is some brown color spotting i noticed but no bleeding. And the spotting was continued till 12th may 2018. Please note - i have donated blood in the month of 2nd week of march 2018. So my questions are. When should i expect my regular period ? When should i took an pregnancy test? Is it normal to have this type of spotting due to the effect of ipill? Or the bleeding was not happened due to blood donation? Please suggest me some answers as i am really tensed about this.please please.please i request.