Brown Cervical Mucus

I'm around 13DPO. Got positive tests at 11,12, and 13 DPO. My period is due tomorrow. I've had light cramping since ovulation. Today I've had brown mixed in with a watery/creamy mucus and then brown when I wipe. Has anyone had this and it been normal? I'm worrying about this leading to miscarriage. I can't get in to see my OBGYN till Monday since it is the weekend. Any advice, opinions, etc. would be greatly appreciated!