Flickering screen crash black and blue screen
***Iphone Background***
Iphone 5s
Running 7.1.1
Carrier Verizon
***What Happened***
I was playing The payed version of Draw Something by OMGPOP when my phone suddenly went to the apple logo. Thinking it just did a "quick crash" and was going to reboot right away, I just set it down adjacent to me. Then the apple logo screen started to flicker and the edges of the screen were black. It flickered rapidly like that until the entire screen went to navy blue with white edges the same thinness as the black on the previous screen. Then the screen went completely black. I tried a hard reset and it immediately restarted the cycle. I did the hard reset again but this time I let go of the buttons after it turned off. I left it to sit for around 10 minutes and tried a simple boot up. It returned to the lock screen and worked as before. The only difference was the center of the screen flickers just a little.
***The Question***
Basically, I want to know: what the problem is, what caused the problem, if possible how to correct the issue or do I need to take it to turn in and redeem the warranty.
Also, I bought my Iphone under a 2 year contract with Verizon at Walmart. Would I need to turn it in at Walmart or an apple store?
Thank you in advance for your time and help regarding my question