lol at lvl 5, you dont have anything to be able to determine what a class can or cannot do.
ill tell you this, pom is a healing class, but currently every healing class is op because they can heal AND do damage. I would say pom is prolly the squishiest of them.
My buddy plays a pom and he says its hard to kill people below around 50, but then it starts getting easier.
The truly overpowered class atm is a Tempest of Set. I am a conqueror, and I get raped every time, I cannot do a single bit of damage to a well played ToS.
Melee is very broken, hard to land combos in pvp, cant out damage their heals, but everyone can out damage my dps. I basically have to have someone stand still for me to be able to kill them. if the person knows how to kite well, its over for me.
As far as conqueror though, i have a lot of survivability. the guardians are better though. i can usually get away from 3 people beating on me if i dont get snared or stunned.