What Causes Chronic Constipation After A Total Colectomy?

I had a total colectomy, due to colonic inertia, 1 1/2 yrs. ago. Have had no problems, and always have very soft stool. One week ago, when I was having my normal morning bowel movement, (which usually is very easy and usually just shoots out), I felt constipated like I was trying to pass a football. It was and still is painful and feels like pressure, like stool is there, but doesn t produce. Is seems like the stool that comes out is coming around something. I tried laxatives, but still having the same problem. I feel fatigued and nauseous, and sometimes slimy, jelly looking stuff comes out. Any suggestions?