First period after miscarriage

Brittany

I MC 6 weeks ago almost to the day. Today my period started again. It just started out of no where and immediately heavy. Although I did have a feeling it was coming because I started cramping pretty bad yesterday and had a severe migraine all day. But there was no spotting, I went to the bathroom in the middle of the night and nothing. Woke up this morning and bam, full force. It's been very heavy and large clots all day. Its this normal?