Hello! Welcome to the forums! Your mage is not attacked when the spell is cast, it is a zone conjuration that "sits" there until some one moves into that zone. It doesnt make a immediate attack, its not an attack spell, its a conjuration, its like you are throwing caltrops on the ground, not at someone.) It only attacks when a creature moves into the zone, so once you move into it, it attacks you, and then you can stand in there as much as you like. and lastly your second question, yes, that is how the spell is made to work, if a creature gets pushed or moves into the zone will get attacked by the caltrops. I hope to have been of some help. If this is not clear, just say so, and I will try and help as much as I can.