I even think 10k hands isnt a good sample size... Its not impossible to be a looser over 10k hands with a 20bb/100 WR.
At 10NL or higher, a good WR is about 4bb/100 if you multitable. Its not impossible to have 100k hand loosing stretches. Rare, and if you have them often the result of tilt, but not impossible.
@OP: Keep plugging away.
Ensure to post hands in the microstakes portion of the forum - its really a good way to keep on improving!