BIG Problem

I ran again yesterday and had a major setback. My calf had been feeling better, but I still made sure I stretched out well before running. The first mile or so was flat, and I felt pretty good except for 1 or 2 times when I felt a little tightness in my calf - but it stopped after a couple steps. Then I ran up a long hill. Just before the top, I took a step and then felt a sharp pain in my calf. I had to stop running (just under 16 minutes) and walk back down the hill to get back to the gym. It really hurt walking down the hill, and it has hurt to walk ever since (especially on stairs). I guess I will take some more time off from running, then see if I can overcome this problem. I am not too hopeful that I will be able to get over this injury and build up to be able to run 13.1 miles in the next month or so before race day, but I'll give it a shot.