I hope this isn't you deciding to use a needle for the first time, as it sounds like you don't really know much about injecting (I may be wrong). It's a downward spiral buddy.
Why not just plug it if you're looking for a rush? I've never used Methamphetamine but do love my Mephedrone which is quite similar in terms of the intense, rushy come-up, and plugging/snorting works great. Sure, IV would increase the euphoric rush substantially but that's opening a can of worms that will be incredibly hard to close.