@susanna82 Welcome to Mayo Clinic Connect! You have landed among people who share your similar health journey, and offer their experiences to show what has worked for them!

As you have found out, changing your diet to one that is lower in potassium, calcium, and phosphorous can certainly help the health of your kidneys. Also, exercising and keeping a healthy blood pressure will go a long ways towards feeling better. The medical community will usually look at the trend of a patient's eGFR [estimated glomular filtration rate = kidney function], not necessarily a one-time value. There are many factors for differing values, including hydration level, and even different labs or machines. And, as you know, everyone is different, which is why we get so much out of what everyone share here.

Have a medical team who you feel comfortable with is crucial. Like you, I just changed to a new nephrologist, and have an appointment with her next week. Has your doctor given you the reason for your kidney disease [hereditary factors, blood pressure, diabetes, etc]?
Ginger