^This. Using fentanyl, especially with a small opiate tolerance, can get ugly quickly. If you put the patch on, then 12 hours it starts kicking in fully and it gets to be too much, simply taking th epatch off won't instantly stop the absorbtion. There will be a substantial amount of fent built up in your tissue that hasn't reached the blood stream yet. This is how many people overdose.
The safest thing to do would be to trade them for something you are more accustomed to like some oxy or something. Otherwise, if you are dead-set on using them, cut the patch into 12-16 pieces and use one at a time, buccally. (In your cheek) This way you'll get the effects much quicker and cna take the piece out if it proves to be too much. Alternatively, if one piece isn't enough, this method allows you to titrate your dose piece by piece until you are at where you want to be.
Fent is dangerous, man. Tread VERY carefully.