Hello I am 8 days late on my period and My husband and I have been using condoms to prevent pregnancy and we have not had any slips so far. And my period has always been regular (21-22) Days. i have been having cramps , swollen breast , and headaches like my period wants to start but nothing yet. I took 4 HPT and 1 Blood test and all came back negative. Do any one no what this could be?