On Suboxone and I reinjured my back

I have been reading this forum for several months and wanted to complement all the great information I have recieved. I am a 30 year old male that is in pretty good shape. I work as a corrections officer. I injured my back on the job 6 months ago and was being prescribed fairly large doses of pain meds. I herniated l4 l5 discs and they were impacting the nerve root. I stopped taking 40mg oxycotin twice a day and 10mg percocet every 4-6 hours last Friday. The pain was some what bearable but the withdrawl was not. On Wendesday my pain managment doctor put me on 12mg of Suboxone a day. 8mg in the morning and 4mg before bed. This morning I twisted my back the wrong way and am in pretty intence pain. I have pain medicine left but my Doctor told me to try taking a 8mg suboxone at 10 am this morning. It didn't help at all with the pain. So getting to my question I know taking an oxy or percocet with not work at all. How many hours do I have to wait until I can take somthing for the pain again. The last Suboxone was taken at 10am this morning 8mg. Also can I start drinking more liquids to try and flush the Suboxone from my system or is that just a stupid question and a waste of my time. Plus I am not looking forward to getting up every 15 minutes to pee with the pain the way it is. If anyone has any other suggestions to speed this process up I would greatly appreciate it. Thank you all in advance.