I Just Had A Termination 10th Of December Just Past,

I just had a termination 10th of December just past, just over 2 weeks ago. Had very heavy bleeding and large clots, because of this was taken into hospital and kept in overnight. Following day I had an ultrasound which confirmed I still have 1 piece of tissue left inside about 15mm but they said it should come Away itself. The bleeding has calmed down a lot but the blood is very bright red. I called a midwife in the hospital where I had the termination and she said not to worry but I can't help but think something is wrong?