The 24-clock prevails in Europe. It's easier to schedule appointments.
Stores close from 1:00-3:30PM, except in tourist parts of town. In the summer, it's the hottest time of day. Stores generally close at 8:00PM.
There's a cultural rule you should learn in order to get to a bathroom quickly. Restrooms in caffés and restaurants are reserved for customers. You will generally, in fact mostly find they are clean and safe. Restaurants prefer you buy a cup of coffee, pack of gum or anything like that to use the restrooms. Think of it as a tip.