Hello Kim and glad to hear your oral surgery went well and I can certainly see how 2.5mgs of perc wouldnt have done much for any pain must less a post op.
I know my surgeons order post op is 2 percs every 4-6hrs around the clock for the 1st 24hrs and then down to 1 every 4-6 until you dont need them. Cant imagine a half.
I sure wouldnt worry over that. Keep getting better and healing and this might be your worst day as it usually is post-op for oral surgeries and by tommorow you should be better.
My thoughts are with you for a speedy recovery