IPhone 4s screen not being responsive?

It was *RANDOM* too
all of a sudden by phone screen is being horrible. First, I can't even slide to unlock my phone, it stops halfway through the little bar then goes to the beginning. So i have to slide the little camera thing up to access my phone. Then, when I click an app I want to go to, other apps open instead of it. ALso, most of the letters on my keyboard are not working. My phone keps glitching and randomly calling people and randomly opening apps. Please help! What's going on? My phone is doing all kindsof things without me doing them.

Maybe broken screen?