Well, They have had the dog for 5 months? The boy is seven months old and you are afraid of him? And you were afraid of him a month ago at under six months old? Well, I can't assess the puppy, no one can without actually seeing him, but dogs are really good at recognizing our negative emotions. He may read your apprehension as something to be afraid of. The barking and growling is most likely a fear reaction to you. He is even more uncomfortable because you are uncomfortable. You and he both need to build your confidence.
And being gone back to school for the next several months means you will come back to a GSD that is even bigger and more formidable, and in its full-blown teenager stage. He may be more mature, and if your parents take an active role in training and getting him more acclimated to people during those months it may not be so bad.
I am not sure what you are wanting to hear, though. After you come home on break, I think that it would be helpful for you to take an active part in training and exercising the pup.
Jenna, RN CGC & Babs, CD RA CGC HIC
Heidi, RA CGC
SG3 Odessa, SchH1, Kkl1, AD
Ninja, RN CGC & Milla, RN CGC
Joy, Star Puppy, RN CGC
Dolly CGC & Bear CGC
Hepzibah & Hannah