Dani, Dani, Dani *shakes head in motherly fashion*
With all the reading you've done on this forum, you must be aware that THE SCALE LIES!!! In fact, it's possible that the scale is an invention of Satan himself, so that us poor, unsuspecting dopes here on Earth will look at it, shake our weary heads and say "gosh, I'd give just about ANYTHING to lose 10 lbs". And suddenly, in a flash of flame and lightning, there he is, rubbing his hands together in glee and chuckling to himself. "Anything, eh?", he says in a used car salesman kinda voice.... "Well, little lady, how about you just sign right here - no, no, no need to read the fine print, just your signature right there". And BOOM - one more soul gone. It happened to a friend of mine. True story.
The moral of this story is that the scale cannot be trusted as a true reflection of your body. 6% body fat is astounding and outstanding and I stand humbled before you. Who cares if it's only 3 or 4 lbs? Well, obviously you do, but you SHOULDN'T. You ran 15 miles. Good heavens girl, that's more than some people WALK in their lifetimes