need help with groin/thigh pain

Please bear with the background info. I think it’s necessary to understand where I am right now. Last March I put down cigarettes after a lot of years of smoking. I was a walker (treadmill and outdoors when nice), but not consistently. My husband is a runner and I decided it was something I wanted to try. The process was slow, but by the end of September I ran my first 5k (slowly. But I did it!!). After this I seemed to be making some good progress. I was able to do a weekend run of 5 miles. In December, however, I developed an injury. My orthopedic doctor was of no help; nothing was broken and nothing needed to be operated on. I did get my general practitioner to prescribe physical therapy. Because I was in so much pain when I ran, I had to stop. I aggressively went at treatment – physical therapy twice a week, regular massages and a chiropracter. All of these people were pretty sure the problem was the psoas muscle. When the problem did not go away after 6 weeks, my doctor ordered a MRI. It showed tendonitis of the iliopsoas (RIGHT side). It wasn’t long after this that I was able to start running again. I was cautious, though. I slowly built back up to between 15-18 miles per week, my usual run being about 3.5 miles. I just started doing a couple 4 miles runs. I haven’t drastically increased mileage or speed, but here I go again. Now the pain is in my left leg. While some of the symptoms are different, some are also similar. I don’t know where the pain is stemming from. It seems to move from my groin (inner) to my knee (a tightness). When I first start running (the first minute or so) it hurts; I get a shooting pain down the inside of my leg with impact. However, it subsides as I continue. It does become very sore after running, though. Ibuprofen helps with the pain. I don’t know where to go from here or who to see. My orthopedic was of no help. Is this something I can “run through” or do I need to stop?? I really want to do the Freihofer’s Run this weekend, but I don’t want to risk another 8 weeks out of running; I really love it. It’s the only exercise I’ve found that I enjoy.:(