I've been on Loestrin 24 for four months now. the first 2 pill packs i had a regular period. The 3rd pill pack I had a little spotting but it wasnt a period at all. I took a pregnancy test and it was negative. Now with the fourth pill pack..I never got my period, not even a spot of blood which is weird and the past few days at least..ive been experiencing stomach cramps, alot of nausea, and breast tenderness. any ideas ?