hmmm - did your doctor say anything to you at your 6-week check up. I heard that it was normal to bleed 6-8 post partum - but I would mention it to your OB at your 6 week post partum checkup and if you already went - call and let him know -they are glad to take questions over the phone (at least mine is) and they will let you know if they want to see you or not. HTH
Heavy bleeding can be quite normal, as you resume your periods. You can have a rough time during the first few months trying to get everything regulated. It will get better though.
Altho its been a while for me I do remember still bleeding at my 6 week Post partum check up.... so i know its not uncommon to still bleed anywhere from 6-9 weeks... annoying I know ... but normal