I started spotting 4 or 5 days before my period was due, I'm on birth control pills and I stated 2 spot on the last day of my active pills, this has never happen and I've been on the pill 4 3yrs now, I had cramping, back pain and leg pains as if I was getting my period but it's only been light spottind brown and first then red to pink but very light, on and off for six days now I took 2 hpt and negative what's going on?