My period was due Nov 5th and I started spotting that night. I thought I was on my period it usually starts off light and by the second to third day it gets really heavy. Well.. it's now day 5 and I'm still only spotting. My boyfriend and I had sex the other night and I bleed very lightly and it stopped. I took a test today and it's negative. What could be going on? My period usually always come right on time every month