I pretty much did levequests I think they're called until I hit 15 theyre easy repeatable and give a crap load of xp!

Work on the main story quest line. Quests open-up in the non-city sanctuaries as you play the story line.

Even if I am in a completely different questing zone? I started in Ul'dah and the rogue stuff is in Limsa Lominsa...?

Quests aren't repeatable per class and so won't be around for all of them. Your best bets for levelling other classes from 1 - 15 are FATEs and your hunting log.

I have gotten my first class to level 15 and I am not leveling a Rogue, I am level 10 as of now but there seems to be a huge lack of quests.... Am I missing something or is there not a lot of quests when leveling the second class?

Hello new to this game some questions...