Hi. I am trying to conceive and my periods are a very regular 30 day cycle. This month I was suppose to start 4/18 but instead began spotting 4/14. The spotting has continued daily (now 4/18) and is barely enough to get on a pad. It is brownish/pinkish red, mostly visible only when I wipe. Also, I have had sore nipples and headaches for 2 weeks. Any suggestions? I took a hpt this morning but negative which I understand is not uncommon. Thank you.