Bloating today, tomorrow constipation

I've been having intestinal issues for a year now, but I'm in a bad spot right now.

It started with severe constipation, then intense bloating and gas every time I ate. I got an ultrasound, and x ray, then a colonoscopy. All were fine except the ultrasound which said I had very small gall bladder polyps.

After the colonoscopy, I seemed to get mostly better, but it's cyclical. I get really constipated, and have to use suppositories every time I go. Then I get to the point where I have to get it all out, and I try smooth move tea or magnesium citrate, both are very severe with the diarrhea, but it only helps for a short time, then I'm back to the suppository route.

Recently, I got real sick, had severe diarrhea for a day, vomited, and have since then, found myself back to the point where the gas and bloating is so severe I'm going mad, and am in a lot of pain and misery.

It seems fiber makes the gas worse, maybe sugar, though I don't usually eat much sugar.

Just before the flu/food poisoning incident, I was on a low carb diet where I was eating less than 20 carbs a day, and I was losing weight (yay!), and my intestines were feeling the best they have in long time, though I still had to use suppositories a few times a week. But the diet is a miserable one, and I can't think that a fruitless/vegetableless existance is right.

Please someone help!! I feel like my tummy is going to explode!!