Dej, when your BP gets too low then your heart rate will increase to try to keep the blood pumping to raise the BP. Even if resting. That's an internal mechanism that seems to be working for you.
When the BP drops so low, it might be not enough fluids in the blood to increase the flow. Ex: like not enough air in a tire will lower the pressure gauge reading in that tire. No enough fluid in the bodies system, lowers the BP pressure. Just an idea from past knowledge.
I found that stool softeners and fiber products did nothing but give bloat and the fiber products extended the intestines. Again without enough fluids, it enlarges the stool size and dries it out, making it move difficult to move along the tract.
Drink plenty of fluids, water is great. I know they try these natural products first. If I am almost impact, due to size and no motility, I take liquid "Milk of Magnesia". I find it gentle. Ask your doctor if you can use that.
When I am full to the max, in the intestines, due to lack of emptying, I have no appetite and belly looks bloated. If I need to get it started I may use a adult glycerin suppository, like "Fleet" makes.
This is just what I do, Gastro doctor is aware and okays it. I am not suggesting you to do this unless you speak with your doctor. I am not sure what you have besides the constipation that makes you toss your cookies. It may be a totally different problem with you. Just giving you ideas what I do.
I, too, gain weight on little food because it stays with me too long. So I make sure the tract keeps moving anyway I can. The daily magnesium works in most cases for me. If not, the liquid works gently. Or a suppository when the urge is there, but with no action to follow.
Good luck my dear.
Nux Vomica
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