Welcome to the board, kondrix! May your adventures in the Gael Serrn fuel fantasies for centuries to come...
As has been said, you can be as many classes as you want. Your journal only shows the last three (or maybe four) classes, but you retain the skills and abilities. And aside from the basic four classes (warrior, wizard, priest, and rogue), you can return to each class after you reset adventures.
In most of my games, I've been just about everything -- ninja, samurai, barbarian, paladin, ranger, warlock, monk, and special (assassin, zenmaster, and valkyrie). My current Den of Thieves game will remain rogues, except for one who will become an assassin. That should be a lot more challenging...
And Willow! I love what you've done with your hair! It smells so much... fresher