How can I downgrade my Android from 5.0 Lollipop?

A

AC Question

The downgrade of Android 5.0 lollipop.

The night of 15-Apr-15 I went to sleep and all was right in my little world. Yes, where was killing over stupid stuff dealing with radical religious people. But my phone's operating system was using about 17% to 20% if my batteries life. My camera had taken many pictures and all were stored on my MircoSD card. My downloaded games (totaling two) were also on my SD card. The interface to my phone, camera, email, contacts and my digital life in general was working.
I woke up to a message congratulating me on what it thought was a successful upgrade. Now I see my operating system is using 41% of my batteries life, my SD card is listed as 'Damaged SD card' and I should try reformatting it (but it works fine in my computer), and the interface to my device looks like a third grader was in charge of the project. Sorry third graders I'm sure many of you are far smarter than this. On 16-Apr-15 I stopped by the Verizon store and they said good luck go to Samsung, but there is nothing we can do for you.
I really need to undo this debauched and rancid upgrade and set me phone to NEVER do that again. Please help me restore me phone and NEVER let Android do this again. I hope everyone that had a finger in this project is fired.
BMD