Not sure why you started with "No sir" but then to "I want my f---ing money". Many on here will frown upon your "lack of professionalism" but it's your right to speak any way you wish, as it is your right to carry a weapon. Just not sure why you lost your cool so quick in this situation. Should you encounter a real self-defense situation, it would be best to be prepared to better handle the situation.
Again, not to criticize, but your tone may have come across as threatening, and while it is your right to speak as you like and carry a weapon, it's generally in your best interest not to come across as threatening when OC.
I'm just a guy, so take my advice FWIW, but I think that when carrying, especially OC, you must learn increased patience. The first time I OC'd was at an Outback steakhouse with my wife. After reading this forum (mostly the horror stories) I was ready for a fight. I had myself all worked up and winded up getting into an argument with my wife before we even got into the restaurant. I quickly learned to be more patient, including most importantly, with my wife.
This situation doesn't seem to have started off too negatively (you were not asked to leave, the police didn't show up, etc.) Personally I would have handled it differently.
For one, especially in cust svc situations, you usually get more flies with honey, so to speak.
For two, it sounds like the store doesn't have a firearms policy, which is why the manager tripped on her words. The way this went down, it may very well result in one being created. That should be the last thing we hope to have happen from OC.
Last, just think about what might have transpired if an innocent passerby had noticed the situation for only a moment and saw an armed man demanding money from the manager in a threatening way (to many people, cursing is threatening, and while cursing is not in itself illegal, it never really serves to "calm down" a situation)... Assuming he means to act, best case is he's unarmed and makes a phone call to the police about an armed robbery in progress. Worst case, he's armed, and means to stop this "crime in progress".
Best policy, IMHO, is to remain polite, or at least invisible (don't go out of your way to give yourself unnecessary attention).