After replacing battery. Home button and front camera stopped working

I didnt damage the cable in any way shape or form I was actually very careful with it maybe too careful but now it just wont work. Even shows the "unable to activate touch id" message. And on top of that it can switch to the front camera because "flash is disabled because ipad is overheating" error that keeps appearing. Any help please? This is supposed to be a friends ipad and geez I tried so hard to be careful this time.