Baffled

C - 6.1 (?), 52:43, push Up challenge

I was so sure that today's run was a lot slower.  When I finished my run I looked at my watch and did a double take.  I then mentally ran through all the streets I ran, looked at my mapped out route on our running mapping program, and even remapped the entire route.  Sure enough, when I mapped the exact same route using the exact same mapping program, it gave me a different distance.. but not shorter than 6miles, longer (not a ton, 6.1 miles to be exact).

But ... I was so tired.  How is it so close to yesterday?

I'm still not sure what to make of it all.  Yesterday felt speedy, and depending on what distance is actually right, today was somewhere around an 8:35-8:50 pace.   That's not exactly a zooming pace, but I was tired today and, yet, my times for yesterday and today on the same course aren't that different.  Yesterday I pushed to accelerate, today I pushed to maintain my pace.  I listened to the same faster pace workout music but gueez.  I keep looking at my watch, but it seems fine and I just replaced the battery a few months ago.  I'm definitely baffled.