salt will increase blood pressure---but if you have a heart condition, your doctor might not want you having salt. If you have been dizzy for three weeks, go see your doctor. You probably should have gone to see him three weeks ago. Low blood pressure needs to be controlled, just like high blood pressure
. When blood pressure gets too low, it can cause all kinds of problems, like strokes. Not trying to freak you out, but you should see your doctor, to find out what your blood pressure is.