Make sure your bandaging between battles and use your /rest skill if your real low.

Gladiator shoudl be able to take stuff out no prob thier same level or a level above them.

As well make usre your checking back with your trainer often for new skills.

You actually shouldnt have much of an issue from lvl 10-15 since your sporting a kick ass polearm you should have got from the trainer after your lvl 10 quest. (turning into a Deva)

Also save your +HP and +Crit Manastones and apply only those to your gear. if you have green gear to vendor dont use the extraction kit and enchant your weapon.

Shoot me a tell in game or grab me on vent if you need help with anything.