Many people including me have had success with mesalamine enemas for lower inflammation. You also sound like you are severely constipated and there is over the counter help for that (Citrucel, Exlax, many others).
If your constipation becomes extremely severe it could cause toxic megacolon which requires hospitalization.
Not trying to scare you but it can cause death in rare cases.
Yes, tenesmus is the name and is one of the common UC symptoms. I was so happy when mine went away due to remission.
See a doctor and describe all your symptoms. Ask specifically for the enemas since many docs forget about
them. They really work.
In remission April 2010 after 10 years of suffering and no remission ever
Jan 2010 started SCD diet (modified to remove dairy, fruit & juices)
Gluten-free=bleeding stopped in 3 days, 95% remission in 5.5 months on SCD
at 5.5 month stage homemade yogurt, milk products and some fruit OK
SCD Diet: Gluten/grain-free, starch-free, low carb, low-sugar
Supplements: tsp. fish oil, Vit D3 5000 with oil/fat, veggie juice, sunflower seeds, VSL#3, (6) Citrucel, (1) turmeric capsule
Highly recommend: the book "Life without Bread" and the Specific Carbohydrate Diet
Rx: (6) balsalazide daily, mesalamine enema occasionally