Hi Betty,

Yes I have had this. I had the problem of drinking too much water due to anxiety, it was also sort of a compulsion. So I did develop low sodium and was quite sick but I did not know that was the problem until I got some uncontrollable diarrhea (sorry, I know TMI) and had to go to the hospital where I was diagnosed.
I was able to get a normal result within a few days by drinking much less and taking some electrolyte supplements.
The ER doc said low sodium is common in marathon runners and is usually very treatable if you don't have any underlying health issues like kidney disease. Just make sure to eat and drink a balanced diet.
It sounds like you are well on your way by taking the salt, I did read about a connection with depression and electrolyte levels so you might want to look that up.
Take care.