Hello, okay, umm, i am almost 3 months late for my period, i took 3 home pregnancy tests and i went to a doctor, all negative, i don't understand, i mean, i'm having all the signs of being pregnant. sore breasts and nipples, no periods, sick to my stomach, moody, i mean, i don't understand what is wrong with me? should i be worried that my stuff is all messed up? or is it possible all 4 tests were wrong? i am 17 years old, i need to know what is wrong. please answer back.