Any ways to get big triceps FAST?

Kickbacks are definitely not enough on their own, you need a variety to sufficiently thrash your triceps. If yo have access to a cable machine, standing cable tricep extensions are a great way to work your tricep. If you don't have access, you should really consider skull crushers, they are great for adding mass and strength to your tricep. And finally, dips are a great exercise for your tricep and shouldn't be overlooked. Good luck.