Concerned and frustrated

Soooooo I've been TTC basically since my 6 month 3 wk old was born and obviously nothing has happened yet. But what confused and irritates me is my lack of a period. I'm spotting almost every month around the time my period is suppose to start but it lasts no longer than two days! AND it's light enough for me to only really need a panty liner. I was wondering if anybody else has had this issue?