Rapid Battery Drain upon iPhone repair/reassembally

Hi, I have a rapid drain on my battery with my iPhone 5s.

I replaced some of the internal parts like the sleep/wake button along with volume controls. I had to take apart a lot of items including the motherboard. I was wondering if there was a way of damaging any of the components in the process upon reinstalling (say by shorting or damaging something on the motherboard, or by even damaging the battery somehow in the process). Whatever the case, it's frustrating and I'd like to fix it. Appears that all connections on the phone are firmly placed.

1. The phone does not produce a lot of heat when it drains.

2. I've replaced the battery to another one an it appears to drain a bit less however it still drains more than normal.

Anyone have thoughts about this?