If I know I'm going against a shaman, like in this situation, I will always wear my lightest weapons and I will try to have my rot strategy in hand. Even if you have to wield avg 18 maces, do it. You've got nothing other than parry.

And why the heck were you not flying? At least make the shaman burn a dispel.

Summoning against a black circle is tough, by the way.