neo_n, shoes are like other clothing, one man's 7 is another man's 9. There's no millimetre-perfect definition of a size and shape. The best thing is to go to a big shop and just keep trying on shoes till you find a pair that fit. Or have them hand-made by craftspeople who don't come cheap, or go for soft shoes like Skechers, which is what I wear.
When I was little my parents often got me shoes that felt tight, and they'd just say that I would grow into them. I always did - but now in my old age I have all sorts of foot problems. It's worth finding a proper fit even if it does take time.