kristin holmes ` uploaded photo after being mistaken for another woman '
in image , 26-year-old is beaming while pointing a gun toward the camera .
she captioned it : ` so you know the difference when you `` come find me '' '
holmes , from virginia , has been charged with harassment by computer .
facing class 1 misdemeanor that lead to one year in jail and $ 2,500 fine .
but she argues the photo was ` just a funny picture ' that ` was n't a threat '
state law bans use of vulgar , indecent and threatening language online .