hey im 16 im on day 36 now of my cycle im havin really bad cramps lower back pains but im not seein any blood i think thats verry strange im have signs dat my period is cumin on an am not seein any blood sumone pls tell me why???/im pregnant??? i took a home pregnancy test yesterday an it came out negative but im havin signs of period an no period, my period is pretty odd last month was june an my period usually for the month runns into the next month!! for example today is july 6 an my period for june which was last month hasn came on yet it normally runs into the next month so june period wud normally cume aroun july 3rd or 1st an i havent seen it yet im haven bad crams from the endin part of june to now ,,,my lower back hurts an i get headaches an my brest are sore why is this??? an wat happen to my period y an i not seein n e blood?? plz give me sum responses