What may cause small hard subtances, and slime in stool? There's been bouts of diarrehia, constipation, cramps

Answer 1

You could have irritable bowel syndrome or Cronh's disease.
Have it checked out.
In the mean time, take acidophiles and digestive enzymes to boost your digestive track.

Answer 2

Cramps are muscles tightening up take a swig of molasses or some bananas for the potassium and magnesium that will help them relax.
Diarrhea/constipation consider anti-yeast, anti-fungal products like turmeric and/or grapefruit seed oil.
For more information on muscles, pain and referred pain read The Trigger Point Therapy Workbook by Davies