If you just received this phone a few weeks ago, it should still be covered by a warranty, yes?
Instead of replacing the screen yourself, why not just have a service shop do this for you? Tearing down a phone even if you have the necessary tools and equipment isn't a trivial task, and even if only some of the costs are covered, it will still be a matter where if you try to do this yourself it will negate any further coverage.
Do you own repairs after the warranty expires.