And down for the count

After my triumphant return to blogging, I've managed to incur some sort of injury in my left heel. Here's how it goes:

S and I went to Washington DC the weekend before Valentines Day, along with a few members of his band, so that they could play a show at American University. While there, I ran an "easy" 3.5 miler in Potomac, Maryland, and then a 9.3 miler along the C and O Canal. (Easy is in quotes, because Potomac is the most hilly neighborhood I've ever run in.) It was quite cold on the canal, but it was a delicious run. I hadn't run more than 5 since getting my wisdom teeth out, and I was so happy to be out with the wind on my face. Thinking back on it now, I felt little twinges in two places - one along the seam of my right sole, where it turned out I was getting a nasty blister (new, thin socks), and one along the inside of my left heel/ankle. I thought nothing of it. It felt like a little bruise.
We came back to Somerville, and I had a nice easy run on Tuesday. Just a quick 3 miler, with little twinges.

Thursday was the killer. I had a 6 mile speedwork run set out for me, which, for the sake of time, I shortened to a five miler. The plan was - 800 warm-up and cool-down with three 1600s at 9:16/mile, with 800 recovery jogs in between. By the time the first 800 was through, I had a twinge in my ankle, but I wanted to power through. That was a mistake that I regret now, though my speed was pretty good. It was the last 800 cool-down that was the most painful, though at other times in the quick miles I did actually make a noise. It felt a bit like I imagine being stabbed with a small pin would feel. Throughout the run I realized I was altering my gait to accomodate the pain - very small steps, and landing and lifting off on my mid-foot. Closer to the heel, even.

I ended up limping for the rest of the day.
I had an easy three miler on tap for Friday, but I ended up going to the gym and using the bike instead. It didn't hurt at all, and wasn't nearly as satisfying as running.

S and I spent the day in Amherst yesterday, and we each had a run planned for today. Mine was supposed to be 11 miles, and his an interval run. We were to meet up at Petsi's for breakfast. I wrapped my ankel all day yesterday, and it most definitely hurt when I woke up. After doing some research, I decided I may have given myself Posterior Tibial Tendonitis, and hoped I would be able to run even a short distance today.

No such luck. Pain when I woke up, and a crushed heart. I went to the gym and did an hour on the elliptical (with some pain), and twenty minutes on the bike. Unsatisfying, disheartening, and boring.

I haven't run since Wednesday, and I miss it horribly. Mainly, I'm scared that the Run for the Border half marathon at the end of March is out of the question.

Any help?