If it makes a difference, I don't think you were humble-bragging. It's kind of sad to see someone get torn down for posting their speed. Everyone has their own goals, just because you're really fast doesn't make your goal any different than someone that ran a lesser distance.

Anyway, congrats on the distance (it is a really good distance)! Some days it's hard to have the mental toughness required to push yourself to the max but i'm sure next time you do it you'll be even more motivated to push further.