It shouldn't take too long to get back to level 35. Focus on filling out your hunting log to begin with – try to battle as few enemies as possible at low levels because you'll use up your "rested bonus" extremely quickly, but it's more valuable at higher levels because you have to fight a lot more enemies per level. Once you get to level 15 you can start running dungeons. Also if you've picked a DPS job this time you should do the Hall of the Novice challenges again to get gear for it. (Assuming of course you've already done Hall of the Novice with your warrior – if not, you should do that now and you'll get a ring that boosts EXP gain at low levels.)

The other option is that as soon as you've got a second class available to you, you can switch to it and back to warrior, and that will reset the beast gauge to zero.