Welcome to HCM
We understand your concerns
I went through your description. Protein is used by body for several functions and it includes muscle texture building and posture, proper absorption of several mineral of vitamins
. building of cell etc. It is quite normal to take protein powder by today's young men and women who are physically active. It gives the needed supplement to nutritious food.
Amino acids (around 20 of them) is also one of essential item for body and body can absorb it quite usefully. As long as glutamine is concerned, it is not so much essential for human body normally. But for extreme athletic and for some gastro intestinal disorders body needs it.
Therefore you don't have to worry if you active physically. As the studies are still on about the side effects of glutamine, nothing is conclusive, and for the time being it is considered safe.
I hope you are satisfied with my answer. Please feel free to contact me on this matter.