I started running roughly about 10 days ago, after many years of not running at all. Before this I have started doing small exercises on a regular basis (pushup, pullup, squats, rowing on erg) about month and a half ago, so I wasn't starting from a real couch potato status. My running routine is stretch first, walk about half a mile, and then start running until I run out of breath. I make sure that I actually run 3 miles, and I usually split into 1.5 miles / 15 minutes.
On the first few days my quads were sore but they got fine afterwards. But in the last several days my groin / hip adductor started to get sore. I thought it would go away soon but today it got to the point that I had to stop in the middle of the run. When I do the butterfly stretching the sore area really hurts. It seems like this is not the usual soreness that first-time runners encounter (more likely to be quads, hamstrings, etc.) so I am wondering if I am doing something wrong, especially in my running pose. I do make sure to stretch my body before running.