What Causes Dark Color Discharge During Menstruation?

Ok I have had a dark well black like color on the t-p after I wipe when i go tinkel. I also have a pretty bad smell not fishy eather just bad. No itching and no pain a few craps every now and then but that is it. I have had my periond this month already as well. The color started mabe 2 days after my perioud. Also my peried was light and normal i have a least a day of heavy. What could this mean I am starting to freak out. I have no health insurance so i cant go to a doc.