I have sort of the same problem but...
Sometimes my button won't click, it just feels kinda mushy and it won't perform an action (go to home/open background apps) or sometimes double clicks when I only did a single click. This happens a few times a week. I took it to the Apple store last week and the Genious told me I shouldn't have so many and certain kinds of apps open all the time (like Facebook) that take memory. Ok, fine I said I would keep my apps to a minimum. After four days it had still happened a few more time. I just went back to the Apple store and the same guy help me. He said he would try to clean the button with compressed air. I asked what I should do if this continues to happen. He said that since it can't be replicated in-store, he couldn't help me. Since this problem only happens a few times a week my concern is that it will steadily get worse but by the time it fails it will be out of warranty. What should I do?