Re: voice cracking
Man, I feel the same way so don't worry about it. That's just a natural way to feel, all guys feel like that at least once! It'll get lower, not overnight, but eventually it will and you won't sound like a kid. It just takes time...when it changes fully, it'll feel so fast and then it'll just be another thing in life that you won't even look at anymore because you have more important things to look to.
I got a question for you tho...why did you scream at the top of your lungs? Your voice doesn't actually break and you can't force it, it's just a term used because it sounds crackly and appears to be broken from it's regular, higher state