I just need to say that I see myself in your post. I remember when Uno was a tiny puppy he was AWFUL! He still is a puppy, 7 months, but waaaay better now. Did he eat his poop? yup. Did he shred pads? sure did! Did he bite me so hard I thought he had rabies??? YES! And I thought I was raising him wrong. But...
I bought Uno the pills "Potty Mouth" from the petstore. Worked like a charm. When he went off of it he started eating his poo again (only if it was on his pad for too long....which I think the "clean den" instict kicked in) so he went back on the pills. Now he's fine, and a non-poop eater!
Don't feed him more though...you'll just make him gain weight.
Trust me, it gets SO much better. I couldn't even hold my puppy without him attacking me, and now? Well, he's asleep in my lap as we speak and loves to give kisses.
There is hope! And don't worry, it IS a phase and you'll get through it. I didn't believe it when others said it, but now that I have become one of them...i'm telling you the same thing