I pretty sure that I was about level 11 also when I did that. I know it soesnt exactly answer your question but I hope it helps.
Poison room. If you have a bow you can go to the edge of the floor and take out the skeletons on the right. You can folow the blood and jump up on a ledge and take out the skeleton on the left.
If you dont have a ghost that can heal you up I would advise to spend a point on that. It helped me quite a bit at lower levels.
Also; I have discovered that 2h weapons seem to be the best to use in this game. But thats just me.
