My mom wont let me take protein shakes because on the instructions it says not for people under 18. wtf is up with that, i mean most people take it when they're under that age.

I don't know how old you are, but the warnings are less a nutritional/biological warning and more a "You're a kid and you're parents need to know what you're doing" warning.

If you're 15 or 16 (or older) there is likely little problem. But do some research, google can be your best friend. Contact your family doctor, even a nutritionist. If you can find research that is backed up by your doctor/nutritionist, take it all to your mom. If you're armed with knowledge, you'll always win.

Its protein, whats dangerous about that!