Hello Ezerael.
Welcome to the board.
I think Doodlebug has some good advice on this matter. I'm not sure if Ainterol or any other pm supplier will deliver to an APO address. Even if they do, I'm unsure of how long it would take to get a package out to you. Getting somebody else to ship it to you from the States may be your best option here.
Coincidentally, years ago I was deployed overseas and one of my duties was working in the mailroom. At the time, the big emphasis regarding contraband items being sent through the mail were items like alcohol, flammables, porn, explosives and firearms. Obviously the military wouldn't want you to be getting illegal drugs, but I doubt there would be any issues with you getting herbal supplements. If I remember correctly, when I was deployed soldiers could get their bodybuilder protein supplements and stuff without any issues. I don't see why it would be different for herbal supplements.
If it doesn't seem feasible to you, I suggest waiting until you're back in the States before starting up on NBE.