Yes, if you've got dark hair there will be a lot of shadow. And because you're only 14 your hairline will still be quite visible. Take it down to a #1 and see how you like it. It will quickly grow back to a #3. If you like the #1 and are feeling adventurous, then go for the full shave. Just bear in mind that there aren't very many 14-year-olds with shaved heads so you'll likely stand out from the crowd. It will grow back to #1 in about a week. Are you prepared to live with a bald head for a week if you don't like it or if your friends tease you about it?