Touch screen won't work on my iphone 5s after screen replacement

So I had accidentally dropped my iphone 5s onto cement and the screen had cracked, nothing major, everything on the phone still seemed to work perfectly including the touch of the screen. Because of the annoying sight of the cracked screen I went into the local shopping centre to get my screen replaced with a new screen (this place was not an Apple Store). When I got my iphone back, the screen was faulty and had a problem with the pixels, so I went back to the store again and I received my iphone back and it was even worse than before, the touch screen went all funny and certain places of the screen sometimes didn't work at all. So the process was repeated and I went back and now nothing will display at all on the phone, its just a black screen and when I press the home button it will come up with a darker blue to show the phone is on. All the sounds are working, its just the touch and display of the screen are not, I've tried looking it up, but I'm not sure if people have had the exact same problem as me and it all seems confusing. Is this the fault of the people who replaced my iphone screen? And has anyone else had the same problem? If so what did you do about it?