If you approach Guild Wars 2 the way you approach WoW, you probably won't enjoy it. WoW is all about the end game...Guild Wars 2 really isn't. Leveling as fast as you can is a sure way of missing most of the game. Try playing it like you'd play a game like Skyrim and you'd probably enjoy it a lot more.
Just a note: I usually don't participate in PvP, so take my "advice" with a pound of salt, I might be wrong.
You don't need to level at all if you only want to take part in PvP as you automatically (as soon as you leave the "tutorial stage") can enter the PvP part of the game and are there levelled up to level 80.
All your PvE gear (weapons/armor) is inaccessible in PvP but you get new PvP armor/weapons.
My best advice for lvling up is explore. You get xp from finding new places. You get xp from finding PoI's in maps, vistas, waypoints. Also FARM make sure to pick up farming tools and when ever you are out and about and you see farmable mats grab them. Farming gets you more xp than killing a mob and takes a whole lot less time, plus it gives you mats to either craft with (which also gives good xp) or to sell which can give you plenty of coin.
As for PvP, sPvP its no problem to go into from lvl 1 as you are 100% lvled up and you get top gear, just know your toon before you go in. You can try out builds and skills in sPvP to see how well they work and can be a fun experience.
As for WvW, the up scalling doesn't always work well, I it's best if you know your toon before you go in because if you don't you will have problems. If you know your toon you can still be at a disadvantage, but not as much of one. The biggest disadvantage you will have is until lvl 30 you won't have all your utlity skills and elite skill unlocked. However as long as you keep your gear lvled up with you (which doesn't matter much in PvE, but in WvW it does) and you know your toon surviving in WvW is easy and as you get more skilled excelling in WvW will become the norm.