Hi sugarfiend,
so sorry for your loss
I would get onto another Dr and get a better answer. Infections after D&C are normaly caused by a small amount of tissue left behind as when they do a D&C they cant see what they are doing and therefore it is possible that they may miss something. Im not sure if there could be any longterm effects of an infection but a lady that was in my belly buddy group lost her little boy at 20 weeks and she had bleeding for 6 weeks after birthing him. When she finaly went to Dr she had a little of the placenta remaining and that is what was causing the bleeding.
I had a D&C in Nov last year, all went well and from memory I think I only bled for about a week but then I didn`t get a period untill about 6 weeks later.
Hang in there and I hope it all works out for you.
Take care.