Possible Peroneal Tendonitis

Today, I was supposed to run the Hyannis Half Marathon. Instead, I'm stuck in bed. I've been told that I've either a) sprained/strained my foot or b) developed a stress fracture. I was so angry at the doctor when he told me that there's a chance that I will be unable to run the marathon. I've been working altogether too hard to pull out now, and I'm not going to quit! If a doctor ever tells you something that you don't want to hear, the next step is to get another opinion. I emailed coach Jack for his feedback. He suggested that it may be peroneal tendonitis or plantar faciitis. I'm going to assume that it's peroneal tendonitis because this is a common problem for those recovering from ITB injuries. The pain is located on the outer ridge of my foot near the arch and on the underside of my foot. It's most severe in the morning after rest. There's some swelling and discoloration. I'm going to stay off my foot for a couple of days until I am able to walk to the pool without limping. Once I am able to walk, I'm going to dive back into my crosstraining because it's important that I maintain a "marathon fitness level."