Skyrim Xbox 360 help? Can't beat Potema!?

I'm level 19 and am on a quest to bring Potema's body back to Syteer. For some reason I CANNOT defeat that Drauger Deathlord. I usually stand in the doorway and let the draugers come at me one by one, but when he shows up, it's like I don't even stand a chance. I've got an inventory full of health items (10HP/each or more) and a coulple potions... I'm also using a Dwarven sheild, equipped with all Heavy Armor.

I don't know what else to do. When I see him running up I shoot him with my enchanted flames bow, and then switch to an Elven blade (I do not have any more weapons- because the guy in the last room had a shout that disarmed me and left me without any weapons). I can get him down to about half health... but then he comes back and KILLS me. I've also used my masture Relenting Force shout, but it takes to long to recharge. OMG, this is driving me INSANE.

My compainion was also killed... any HELP?!