ShootingStar, go online and search for reading glasses for small heads. I have the same exact issue as you, and I buy my reading glasses online. I also wanted fashionable, funky ones and it was virtually impossible to walk into a store and buy the off the shelf funky ones. There are frames that are made for "tweens" that you could try on at an optical shop, but they will cost a lot more.
I had more of an issue when I wanted to buy fashionable frames for my progressive lenses that I need to wear on the rare occasion I don't have my contacts in. After getting some help here on TE, I found a brand that had a line of frames for small heads and a place about 15 miles away that carried them. I ended up getting a different brand, but found a great optical place. So different than the place I was going to where they told me what I wanted doesn't sell with the stodgy suburban women around here... guess I'm an outlier.