Way to go Mrs. Dork. Bite the helping hand.

A few points

Why did the door greeter have to come running after you?
Why didn't you tell her at the start that you brought the rug in to do a color match?
You didn't you even mention it until she tied your bag in a knot.

Then there was more back and forth and you called her a name as you walked away.
“Why else would I bring it INTO the store, duh!”. Uh... shoplifting 101. It's their job to watch out for that kind of thing.

So then you decide to leave, and rather than just leaving, you take the rug out of the bag, pull the sticker off the bag and stick it to the top of her stand. Any commentary go with that?
So she slammed the sticker onto your shirt? Did she knock you off balance with the blow?
So you pushed her head really hard from behind. Apparently you don't have any problems touching other people.
Then when she stopped, you turned around and taunted her.

Then you come on the forum and smack the greeter right across the face. She doesn't deserve that crap, and if you truly do want learn to be mellow your going to have to learn how to apologize and you should start by apologizing to Rapunzel. There is a reason they call her a “Wise” Elder. Not that you took the time to notice.

About the store
The mellow person that you “say that you want to be” would have walked up to the greeter and past a little smile, “which more than likely would have received a return smile” and made them aware of your intentions and there would have been no problem, “Been There Done That”

My grandfather was a raging alcoholic, my father “unlike most of his siblings” said: I don't want that life for me and I don't want it for my family. “He broke the cycle”.