I know how hard it can be to do 3d modelling, I'm currently taking an interest in it myself and all I have to say to you is no matter how many mistakes you make, hang in there, it's going to be difficult and you are going to -blam!- up lots but just keep going no matter how long it takes, you will learn a lot of skills from it and be on a path to becoming a graphic artist who is well respected for his work, I am Currently working on learning how to make full 3d models of anime Characters in blender, it took me 5 days just to make the chick im modellings face, but once I was done it felt so good to say "hey I made that", it also felt good to see that other people were enjoying my hard work as well and I really enjoy doing it no matter how tough it gets, I hope You will end up doing the same