Brief Answer:
Details below.

Detailed Answer:
Hi
Thanks for asking the query,
Have noted all your details.
Most of the baseline tests including colonoscopy is normal in your case.
Most likely cause of severe constipation along with spasmodic pain in your case is disturbed bacterial flora of your intestines.The mucosal surface of the human gastrointestinal tract is colonized by 1013-14 bacteria of 400 different species and subspecies.They are responsible for proper digestion of food.Once this flora is depleted by toxins released by bacteria many of G.I symptoms like bloating belching spasmodic pain constipation etc can be there.The bacteria in our gut is considered beneficial, helping us digest all kinds of food.The bacteria inside our gut influences our maturation, immune system development, metabolism, and production of essential biocompounds.
Intestinal flora are types of microorganisms known as probiotics that live normally as part of the intestinal tract. These organisms have several functions that help the body.The most plentiful and important bacteria in the small intestine is the Lactobacillus species. Lactobacillus helps ferment indigestible carbohydrates. It also helps to stimulate the digestive process and aid the absorption of nutrients,as well as increase the motility of the gastro intestinal tract.
I would suggest you to start taking probiotics for few weeks.Probiotics are live bacteria and yeasts that are good for your health, especially your digestive system.As you gut flora will improve your constipation would be relieved and well formed stools will pass.
Add lactulose 10ml once daily for few days to soften the stools.
Apart from that some general measure that will relieve you are-
thrice daily , take two tea spoon (or one big spoon) isphagula husk with 200 to 300 mL water
- increase warm water( atleast 8 glass/day) intake
- do not drink water during and after meals
- eat small meals (rich in fiber)
- eat plentiful of fibrous fruits.
- avoid COLD milk and and AVOID junk food
- mix few drops of "lemon juice" in warm water. Drink on empty stomach, early in the morning, to aid in bowel movement
- avoid aerated drinks.
- do some exercise early in the morning
- take 2-3 spoon edible virgin olive oil in the morning
All these things will increase the bulk of your stool,Will soften it and will clear your ileum of the compacted faecal material.
Follow up after a week.
Regard,
Dr Ramesh.

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