One extra mile, by itself, shouldn't have made much of a difference. But was there anything else different, or more difficult, about that 7 mi run? For example, did it include a lot more hills than usual, or perhaps were you going at a significantly faster pace? Hopefully your knees have recovered since then.
"...I've learned that you shouldn't compare yourself to the best others can do, but to the best you can do....I've learned that you can keep going long after you think you can't..." --- author unknown
2013 highlights...
@ 5K:
Ontario Mills 5K, Ontario, CA, 24:42
Heart of the City Run, Los Angeles, CA, 24:13
Downtown Anaheim 5K, Anaheim, CA, 24:32
@ 10K:
LA Chinatown Firecracker 10K, Los Angeles, CA, 51:42
The Great Race - Old Agoura 10K, Agoura Hills, CA, 51:12
Fiesta Days Run, La Canada, CA, 49:31
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