Unable to launch phone app from home screen

I am using IOS 5.1.1. Over the past few day or so, I've noticed I am unable to click on the phone app on my home screen to launch it. The only way is to use spotlight search which is a long winded way. I can find the phone app if I move my finger to the bottom left of my home screen, however if I swipe left and right then voiceover skips over the phone app as if it is not there. The only thing I've done recently is to test out a portable battery charger but not sure if that could have had any effect. I did have another problem the other day whilst I was using the charger and I tried rebooting the iphone. It ketp going into a non stop loop where it kept saying voiceover on every few seconds but not had that since. Any help would be appreciated.