Sorry, what have you done, precisely?
Are you sure you did everything right in the home button re-assembling with the new gasket?
You have to make sure that the home button positioning is the same as before with the new gasket, so hold it in place when you position it for the first time (so the adhesive can stick to the screen).
Finally screw the plate back on.
Then, if your screen is not defective, there should be no problems, really.