I think how you're describing the smell is pretty accurate. *As I take a big whiff of this bag I have here* I would describe it as a musty, chemical odor, possibly a hint of an old plastic bag type scent that could only be produced by a human. I can't think of anything in nature that it could possibly smell like. The smell should be strong and overwhelm your senses. I think that's all I have for my description lol. But it does seem like your shit is legit, maybe just give it time before you doubt yourself. I kind of felt the same way with my very first batch, but I think it was all in my head that I was the one who made it and of course I had a million thoughts going on about it. Then I had a couple buddies try it that didn't know it was home brewed and of course saw great, and I mean great gains (and it wasn't their first rodeo with gear). My only advice is to just give it some time, if your not having swelling, any signs of infection or abscess I'd personally keep shooting it just see what happens. Keep your head up, don't be doubtful so soon!