Expanding my mileage

As I am getting ready to run a half-marathon (13.1 miles) on May 31, I'm in the process of ramping up my miles in training so I'll be ready for it. At the same time, I'm attempting to walk the fine line of not doing it too quickly so as to strain and injure myself. Last Saturday morning I ran 11.3 miles, comfortably and relatively easily. This Saturday I intend to do the same. Race director Hal Wolfe assures me that if I can do that distance, the half-marathon will be "well within" my range. I hope (and trust) he is right!