has this happened to any of you?

So I gave birth almost 10 weeks ago. I got my first period about 4 weeks after birth. I'm supposedly start my next period in about 4 days but I have A LOT of discharge like I'm ovulating... I had this much discharge when I first found out I was pregnant.. I took a pregnancy test a week ago just to make sure I wasn't before I started my birth control pills, and it was negative.. if my period doesn't start should I take another test, or is this normal? Has anyone had a period after birth then have it stop?