meco3805,
As to the kidney, there are many people who have lead long, normal lives with only one kidney (people who are born with only one kidney). Many people who have lost a kidney due to trauma, also have no problems. You can live very well with only one normally functioning kidney.
However, if the kidney is diseases, then that disorder may affect the remaining kidney. So, when a kidney is removed because of renal disease, it is a little bit of a different story.
You should be evaluated by a physician, for all of your symptoms. These are questions that you should be asking your physician.
Good luck.