Running won't exacerbate the injury*, but if the movement hurts, I should just slow down or walk. The only treatment for this is rest, anti-inflammatories, heating pad etc. It hurts as much as a broken rib and is treated nearly the same way-- with time. She did tell me to hug myself before coughing or sneezing to minimize pain.
I'm glad I went in and ruled out anything serious. I was pretty sure what it was, but I am happy with myself that I played it smart. So I am back to running tomorrow. I think I'll wait a week or two before I start adding in my hill repeats and speed work. Nice and easy is the motto of the week.
Thanks for all your support and well-wishes.
*For those of you who missed it, I went water skiing last week and through either a fall or twisting or overexerting, I injured my chest.