we had sex a week before she was supposed to have her periods. she took i pill within 3 hours

hey.

i had sex with my gf almost a week before when she was supposed to have her periods. she took i pill within 3 hours after intercourse. her periods for first month were delayed for a almost a week. but now a month later she was supposed to have periods again but there are no signs of it. she is taking cinnamon for reducing weight but she started taking it only 7 days ago. i am worried about the situation why is she not getting her periods. is she pregnant? we have not undergone pregnancy test but she tested it at her home with sugar and per the result she was not pregnant and even she got her periods so we did not bother to test but now more than a month has passed since her last dates. i am also worried about her health.is this situation normal or something to worry about?