Lull

I hit a lull. A wonderful, beautiful fall weekend - and I was just wiped out. Too much training? Too much other life? I ended up not running until yesterday, following last Friday's 7 mile tempo/interval run. The Friday run was good - I did 7 miles including 1x1;1x2;1x1 mile intervals - all at about a 6:40 pace. Felt fast. Saturday nothing. Sunday 1 hour strength. Monday nothing. Tuesday 5 miles easy. Today??