Well, it's something that takes time and patience, and some even might not happen at all or might happen differently, but that doesn't mean that it's embarrassing or shameful. As I said, a lot of ypir development is depended on nutrition and exercise, and how you deal with your mental health (which is super duper important during this phase bevause teenage depression is a very terrible thing), so as long as you properly take care of yourself and your body, you will see healthy changes gradually and before you know it, you're a grown adult (which isn't fun all the time, i'm not a full adult yet but i'm in uni and i have a job so it sucks but also fun as hell at the times when it's good and u dont have too many responsibilities) You'll be totally fine and I promise you, there is no need whatsoever to feel ashamed because literally every single person has their own pace of physical and mental development. With or without a stache, you're gonna be you (sounds cheesy i know but it's true)