Suggest Remedy For Delay In Period

hi doctor my fiance always had 28 days menses cycle , her last period occured on 30th september so her nxt period cycle was on 28th of oct but we were having sexual intercourse on 26th of oct , so when i get inserted to her she started bleeding that means 2 days before the normal cycle and i had stopped there( not ejaculated), after that on 4th november i had unprotected sex with her and within 10 hours i gave her i pill . But she is 8 days delay to her periods ..i had 4 tym home pregnancy test with gaps, last tested on yesterday all negative.what will you suggest?