shooter - ya did the right thing. Lots of people panic and freeze when the bullets start flyin' and you either have to knock them out and drag them or just drag them by the danged hair to get them to safety. You need to give your girlfriend a crash course in bullet resistant obstacles.
Now, as for your small handgun - forget the small stuff, few of them have the power necessary to reach out beyond 'face to face' distance and slow or stop someone. I have 380s and 22s and the like but unless I am right next to the target neither have suffiecient power to reach out there. The next caliber up the pike is the 38 spl - and if that is loaded with heavy bullets (my favorite is the 200 gn swc) it will do the trick a lot farther out than many would think.
This is not to advocate a snub-nose 38 against an AK-47, by any means. But, if your back is to the wall and you have no place to run and that sob is advancing on you, you are in much better shape than you would be with a kal-tec or some other pocket rocket.
If what you carry now is a full size 10mm and that's too big for concelaed carry for you, go with a Commander sized semi-auto in 45, 10mm, 9x23mm or 38 Super. Either of those cartridges will save your bacon all the way out to 50 yds or better if you are in one of those situations you can not extracate yourself from. My two favorites are the 45 Commander and my 7.62x25mm Tokarev. HTH. Mikey.