Musky foul odor coming from open wound. does this mean it's infected?

Odor not always bad: An important part of wound healing is inflammation so the wound area gets red, hot, swollen, tender. There will be drainage. Since this drainage is organic, it loses its blood supply and will putrefy (rot). This is absolutely normal and part of healing wounds. Unless the wound is getting worse, the odor is meaningless. Clean it gently, keep covered with clean dressings changed every other day.