IPhone 5, what does my limited warranty cover?

I have an iPhone 5, and the lock button doesn't work very well, and, I want to fix it. Does my limited one year warranty cover it? Can I fix it myself?

It covers everything except accidental damage like dropping it, or water damage. They will fix it or give you a new one on the spot, did it yesterday for my moms iPhone 4, the left earphone dosent work for any earphone.

Everything just dont do anything dumb

how long is it covered