Resistant proctitis????

I have been suffering from a proctitis flare up for almost 4 months now. Things became worse when I injured myself w the tip of the enema. So, both my GI and surgeon decided I should switch to suppositories ( which have never been effective) and I take 4g oral pentasa. In my last visit to the colorectal surgeon, he added metronidazole suppositories for 5 days. I took it w pentasa supp and things started to become manageable. After the 5 days elapsed, I'm suffering: the rectum is very much swollen from outside, there is dull stabbing pain going up my rectum, I can't either sit or lie down and my bms are almost watery. So, I called the surgeon and he told me that this is called "resistant proctitis". He was very upset and told me that I usually responded to meds and told me to repeat the metronidazole for another time only. Did anyone have this before? How was it treated?
Any advice will be highly appreciated.