As per the responses above, call your Dr if you're concerned. It is possible that extended bleeding can indicate an incomplete d&c, but I'm not sure what qualifies as "extended".

I had fairly light bleeding after my d&c and then 1 week after (Sunday night after d&c previous Monday) suddenly had heavy bleeding. That tapered off after a couple of days and then another week later (the next Sunday) it got heavy again. The bleeding then stopped altogether a few days later (17 days bleeding total). AF started 5 weeks after the d&c.