This could mean that you have an infection in your wound. The brown blood could be pus which has mixed with blood hence the brown color. You should visit a doctor so as to avoid any serious wound infections. Early treatment is good.
It's always good to be cautious w/wounds that needed stitches. The blackened blood (dried blood) could be the wound trying to scab. As your skin is trying to grow skin back around where the thread went in & out of your existing skin. It should be o.k. That's what my body did when I had stitches. The puss, well, try to keep your hands off it. The whole area is going to be really red and sensitive. If you are concerned, you should call your doc. and in the meantime, try gently w/a cotton ball put some hydrogen peroxide on it. I hope your wound heals nicely!
Old blood is commonly brown, color caused by heme elements in blood becoming unable to hold oxygen as a result of heme becoming oxidized (as in rust). Methaemoglobin is the term for this, which is more brownish and cannot transport oxygen. A little bleeding is expected; if it continues longer than a day, consult your physician or earlier if there is swelling or a temperature.