Placenta remains?

I had a premature delivery of my baby at 6 months (miscarriage) 10 days ago... The placenta came out with the umbilical cord few mins after my baby came out. But the next day, while still in the hospital ward, i have a piece of placenta hanging out from below there, and the doctor had to scoop out the remains which is the size of my palm. The past few days, i still have bits & pieces of placenta (definitely not blood clot) coming out, followed by a heavy flow of bright red blood... Is that normal? Do i have to go to the hospital to get them remove everything as soon as possible? Or do i just let it be?