Miscarriage and bleeding

I miscarried naturally November 12. I bled for about a week and then it slowed to spotting. Have been spotting every day since then. Now last night I have off and on had heavy bleeding, especially when using the bathroom. Sometimes I will have hardly anything and sometimes it's a lot. Is this normal? I am supposed to be getting a call back from my obgyn's office. I am worried about something being wrong.