in the end, it was a good outcome for the ladies.
but.....
they did several things wrong you can learn from:
keep the gun on you, not under the counter.
use both hands to hold the pistol.
get a full capacity, full sized 9mm pistol with good JHP ammo.
keep shooting until the threat stops attacking you.
call the cops when the threat is no longer a threat, not while you are trying to shoot him.