Cherished - aghhh bleeding is so horrid in pg. I am the QUEEN of pg bleeding and i can certainly reassure that it is not always the end. This pg i bled continuously from 5-16wks with bouts of extremely heavy clotting etc.This baby even stuck it out through the m/c of her twin so some of them can be very tough indeed.
I do think a trip to the ER is warranted. At least you will know whats going on. You certainly may see a HB even at 6wks. I have seen 4 of my babies' HB's clearly at 5w6d