if ya still want to try diaphram calls and your new too mouth calls. Go to a single reed. its easier to use for beginners. and when your comfortable w/ it. and have master the single reed goto a double and move up so on and so on. mouth calls can be difficult to use if your new to them. they take lots of practice to master. also, try getting an instruction video or audio tape on mouth calls. they will help you on how to make different calls with your diaphrams.
Good Luck !!!