Still Not Reaching New Standard

Today was the "easy" 3 mile walk. My heel is feeling better, though I still am using a pad on it and wearing heel-less clogs to work.

Mile 1 - 11:44
Mile 2 - 12:06
Mile 3 - 12:16
Average Pace - 12:02 minutes per mile * New PR
Total Workout - 36:07

Almost got my pace to 12 min/mi but the consistantly slower miles are concerning me. I'm thinking that maybe I haven't measured the course accurately.