ok so my period in early november which was late for the month october and my period wasn't right it was brown, and then a pinkish color. I read somewhere that that is called implantation bleeding i guess. then since then i haven't had my period. so im very scared i might be pregnant. but i took a hpt and both came out negative, is it because the hcg hormone isnt present yet and i tested to early? does it vary in different women when it shows up? because i've been reading around and some women didnt find out they were pregnant until like 2-3 months pregnant. So any thoughts on if i could be?