Welcome to OCDO! Don't worry too much about the general population, it's those extreme cases we have to mentally prepare for. Most people don't even notice it, and of the few who do notice it you have starers, the questioners (both plus and minus), and the few fanatical anti's. In seven months of OC'ing, I've had three cashiers ask me about it, (usually what kind is it, or what caliber) and thats about it.
For the Starers, I just go about my business.
The Questioners either ask what make, model, caliber, you have, or, they'll ask why do you carry. It's good to be polite, informed, and ready to discuss why you carry, sometimes you can win over someone on the fence about firearms and our 2nd Amendment Rights.
Then there are the fully fanatical anti-gun folks who you cannot reason with, and it is pointless to try in most cases.
So, know our Laws, know Why you carry, and know when to agree to disagree.