What Is Meant By Old Blood Bleeding After A Umbilical Hernia Operation?

I'm 30, 225 and have a 20 month old and a 7 month old, both c-sections. I had an umbilical hernia repaired 2 weeks ago. The healing process has been fine up until about 4 days ago. I've been bleeding dark red almost brown blood from a corner of the incision. I saw my surgeon yesterday and he said it was old blood. What is old blood? He said there's no infection and it should stop in a few days. It's been bleeding pretty heavy now and he jus said when I contacted him is 2 change the gauze more often and use betadine. Should I go 2 the ER cause I may need a stich or 2? Am I bleeding internally?