Easy 10 Became Slow 10

Today was a hard run. I was tired. I thought I was ready. But maybe it was too close to my long run Saturday. I don't know. The temperature: 48 degrees. Sunny. But windy. Very difficult for me to run in the wind today. I just didn't have any energy. Only had one Innergy disk on. Last night ate leftover steak and a yam. Yeah red meat. Doesn't work too well. Breakfast 2 poached eggs & sunflower-honey bread with jelly. Lunch and snacks apple, turkey sandwich, apple & water.
Right at the beginning of the run I couldn't keep up the 12:36 pace. Also different - no performance enhancement before run at Muscle Works. This is a huge part of my running well I believe. The one thing I did do. Never gave up. I ran 2 / walked 1. Non-stop. I just didn't do it fast. Fuel on board GU & Shot Bloks & 2 water with Prolytes. 
Here are my stats mile by slow mile: Mile1 12:36 Mile2 12:40 Mile3 13:16 Mile4 13:12 Mile5 13:29 Mile6 13:51 Mile7 13:45 Mile8 13:40 Mile9 14:12 Mile10 13:08  Total miles 10.12 Time 2:16:00.