phone wont turn on after getting screen replaced

My phone screen cracked a while back and I decided to get it replaced while I was on vacation. After about a week the phone would not turn back on. The power button was giving me problems for two days before it completely just turn off on me. My phone was purchased in Canada and replace in Ghana could they have used the wrong screen and caused damage to it? Is there anything I can do to get it to work again? I haven't had the phone for a year yet and I don't think the warranty will work since I changed the screen.

Please help