Periods after a MC

I had a MC during April of this year, and when I got my period 5 weeks later it was normal. Light and no clots. But now I got my second period since then and this one is extremely painful and there are many fairly large clots And heavy bleeding. Is it usual for the period after MC to be normal and then have ones following that are like this? I am going to make sure I go to the doctor, but I'm wondering if this could possibly be another MC or just a messed up period.