I am in the same boat as you- except I had to take a two day break b/c my nipples were bleeding and severely cracked.
At some pointtoday I am going to give it a whirl and just corss my fingers. I don't know if I should try a different position or go back to the one that was most comfortable. I won't lie- I am a little gunshy but I am also dying to get back into it. So I think you just put him on and go!
And I would guess that you should discard your milk if yo uwere dealing with an allergy.
GL!