Cramping right calf started in lower shin 2 days ago & now in the back knee. not swollen, red, or warm. dr said it's from running. still worried dvt?

Not likely DVT: Your description is not a common one for a DVT. As your doctor said, it is likely from running. Feel your leg again; if you feel cords under the skin that are painful and not associated with muscle, have your doctor look at it again.

Pain: Possible DVT or possible Bakers cyst or possible muscle related issue. The most reliable test to determine the presence or absence of a DVT would be a venous duplex ultrasound.