I get scared again if I haven't done it in a while. Really, no one cares, but if they do so what! Have in your mind that if they give you a hard time you are going to ask to speak to the manager as to why they want to lose you as a customer.
TotallyAwks, you can, of course buy it all online. That's how I started out, and I bought a number of things that are nowhere even close to the right size for me, which I would have noticed if in person. I just bought my first girl shoes that actually fit today, OK, they're just flip flops, but they fit great and are all gold and sparkly. I got them at Kmart and even had a guy cashier. Didn't say anything, they rarely do, got to watch out for old people, they are the most likely to say something.
Followed up with this at a Walmart I hadn't been to before that had a self checkout. Maybe you should look around your area to see if they have any.