Did you use 'top up' water? It's possible that your initial gravity reading may have been skewed if the wort wasn't mixed well. It does seem a tad high, but not unreasonable.
Unless it tastes 'hot', I wouldn't worry too much about it, but I understand trying to determine where and why things didn't go as predicted.
I did a quick and dirty plug in to an alcohol calculator (for extract): http://www.brewersfriend.com/extract-ogfg/
and it results in an approximate OG of 1.079 and FG of 1.018, with an ABV of 7.96%. That puts you right in the ballpark. Accounting for temperature when making readings may put you spot on.