So 2 nd post grad run and it's not going well. I was really looking forward to getting out this evening not too hot no wind and I felt good ( or so I thought) any way usual warm up and off I trot but disaster at less than 10 minutes my legs would just not work so I had a walk, then tried to run again and again a couple of mins later back to walking and on it went like that for 30 minutes. My legs just would not go my calf muscles felt horribly tight, my legs in fact all my body felt awkward as if it has never run in its life. I only covered 3.4k in my 30 mins and most of that was walking, what's going on and where do I go from here??