so my last cycle was 2 weeks before christmas, i have still not had my cycle for this month ive taken 3 pregnancy tests and they were all negative even though my brests are very swollen and very sore , i have alot af back pain while im trying to fall asleep, i have some cramping but not like my period, i cant eat as much as i used to be able to with out feeling sick, im also getting dizzy could i still be pregnate even though ever test said negative