Now i see!
That is a hand!
Her hand with the black glove graving the soldiers rifle! to be more exact.
Man what a cryptic last panel, but it is easily solvable if you zoom out the image and let's us see the rest of her arm, and actually use some contrast to make the hand more defined, since as it is now it looks like the shadow of a person doing yoga.
Well nothing more to say here, everything else looks good, minus 2 starts because i can't stand that last panel, but good work overall.