Battery problems after fix

Hey guys I replaced my iphone 5 screen after cracking it and since my battery has been really bad... Kinda got carried away on the fix and wanted to see everything inside and followed the dismantling guide on the site and took pretty much everything out. Everything works fine now that I've put it all back together just that the battery life is awful. I've also noticed that I can get a tinny electric shock if I hold the phone while it's charging and touch for my laptop. If anyone knows where I probably went wrong while putting it back together again it would be much appreciated. (I know I must sound like a complete idiot and I apologise in advance)