I am kind of going through what you are going through but hopefully I can offer some help. My situation is a bit different as I am constipated to my ribs and couldn’t have a bowel movement for 2.5 months. After several trips to emergency, 4 X-rays, an emergency colonoscopy (to check if I had colon cancer), every product on the market including bowel peeps, I have arrived at walking, prune juice daily, and lactulose (90 ml/day). I am experiencing all the pain and discomfort you are plus nausea... It’s awful! I am currently waiting for a referral to a GI. My suggestion would be have a colonoscopy to see if you in fact have a blockage and ask to be referred to a GI. In the mean time I’d try 16 oz of prune juice a day (but be near a washroom) and exercise and the lactulose at the high dose and some patience.