@heracleums: Mmm...well ok, I changed it. By splitting the sentence, it should be interpreted following way:
"I did wonder (one second ago) if I fired (one minute ago)... Now (at this moment), can you tell me, can you confirm me if I really did it? (one minute ago)
Nice and flowing smoothly. I 'now' wonder if a mother tongue would find curious the time references: wondering in the past for a present action :) but that could be easily explained if you're presented the chance to travel back in time and relive the shooting scene?