Vegan with a slow colon, help please?

Ok, here's what I eat: brown rice with flax, gfruit, apples, plums, cherries, gs, cantaloupe, watermelon, swiss chard, broccoli, carrots, bell peppers, onions, summer squash, tomatoes, spinach, hemp protein powder... I suffer from constipation, food sensitivities (gluten, soy, corn, nuts and seeds) and a continually bloated abdomen which is NOT ok because I model. I had a colonoscopy and was found to have a beautiful colon (I know, what?! gross) but a slow one. I don't want to go on meds. What can I do? I drink plenty of water, only two cups of yerba mate a day, no salt. I exercise. I've started with some digestive enzymes, but I don't know what else will help. Should I add egg whites back in the diet and try to cut back on some of my fiber? I don't know if I could do it. Please please please help me.