I need some help...

Having smashed the front screen of my TAB 2 10.1, I ordered a replacement screen and have fitted it. Now only the middle of the screen seems responsive, the edges, in particular the bottom where the home button etc. are is completely unresponsive. I'm pretty confident I've fitted it OK, because I fitted one (of the wrong size, for 3G models) the week before and that one was completely fine.

Any suggestions?