You may benefit from a good trainer. Especially if you have trouble controlling him at this young age. They really need to be under control and it's best to prevent issues by teaching them this from an early age on. We all have pulled out our hairs when raising GSD pups but by getting help if needed, patience, persistence and having a good sense of humor, you will get here (in about 2 years). Don't forget to enjoy his puppy hood and laugh at adolescence once in a while.