My girlfriends last period was on 9 october. We had mutual masturbution no penetration on 13 october.her cycle length is 27 days so expected date was 5 november but today is 13 november and still there is no period she experience cramps sometimes and got pimples which comes before period usually.yesterday in the afternoon she did UPT and only one clear C line appeared nothing on T. Also today with morning first urine got the same result only one clear line nothing On T.what may be the reason for missed period?It is possible that she is pregnant but test is giving wrong?her cycle is regular.