It can be nerve racking but what helps you out is doing story quests as a warrior/paladin and your class quests to. They will help break you in as a tank until lvl 30.

This game doesn't really leave you hanging on what your suppose to do unless you did nothing but fate grind. Then uh... yeah, your going to be left wondering whats going on. It stays like that until level 30 or hakke Manor, then you have to be really on game and start asking other tanks how to be a better tank.