I'd say go Annihilation until mid 40's then try out carnage if you want to, I would avoid playing Rage spec unless you enjoy mashing keys without much/any thought.
with Annihilation, Keep ravage on CD, always be using Deadly Saber off Cooldown, and keep rupture up.. not to much more i can suggest while you're such a low level... also as you level up it'll only get better with a ton of Survival CD's which if you stick with it you'll find out.