[epow]

You were completely in the wrong here.

Not necessarily, IMHO that is.

I don't know anything about the situation other than what SWAMPSNIPER posted, but in the metro Atlanta area I doubt that many people would blame a convenience store clerk for drawing a gun if he saw a scruffy looking "customer" with a concealed gun in his store. That would be another situation where it would be better to be judged by 12 than carried by 6.

[SWAMPSNIPER]

The issue to me is being able to draw and defuse the situation without going into a panic, and blasting away. I know you were probably taught not to draw unless you are going to shoot, I think my way is better. I don’t want to shoot anyone, but don’t want to be shot myself. Why let things go too far, when there is a chance to stop, before someone gets hurt?
I’ve spent large chunks of my life in harms way, not going to argue about how I lived through it. Most of the time I didn’t have an instruction book.

[Navy Patriot]

in the metro Atlanta area I doubt that many people would blame a convenience store clerk for drawing a gun if he saw a scruffy looking "customer" with a concealed gun in his store.

Yep, you were right to draw, here's why:

A convenience store is private property, the owner, or his representative decides who can carry.

Ideally the establishment would be posted, but it's still trespass for an individual (except law enforcement) to carry when privately restricted.

Undercover isn't law enforcement to the property owner 'till he shows his badge.

Your actions, given the specifics of the situation were reasonable.