I'm determined to and have less skills than you! Forget about them for now untill next year when you can re-apply, focus on becoming a pilot if thats what you want, if your 160cm+ apply for JQ international do as much as you can so that you are really prepared and have shown by next time what you can accomplish in order to become cabin crew for them!
Lots of very young people like ourselves (being only 18) get turned down. Just keep trying!