Frustrated with iPhone 6, unexplainable split screen.

I have had my iPhone 4s for just about 3 years and I have been very happy with it. Lately though it had had some issues with software and battery so I decided that perhaps the time had come to upgrade. I upgraded to the iPhone 6 with a bit of trepidation because I seem to be one of the few people who prefer my phone smaller.

Anyway I took immediate caution in protecting this new phone. I had the 4s for 3 years and it had not broken once. I take pride in that. Therefore I went out and immediately bought a case for the phone. 9 days after my purchase I looked down and tried to move what I assumed to be a hair off my screen. It was instead a crack looking almost like a clean cut with a razor blade slashing its way across my screen. Now as someone who had not yet dropped the phone nor had ever had a phone crack before I was understandably upset. I am to a point where I jo longer want this large phone!

Although the extende battery life is nice it is really he only benefit I personally reap from this device. I am sick to my stomach that there is a crack and I cannot even explain its appearance.
At this point I just want to go back to my 4s I don't trust the 6. As a loyal att customer I refuse to believe I don't have options, I just need to know what they are. Options? Opinions?
Has anyone else had this problem?