I would say yes Kay check out all of the above and check out any environmental allergies ..They are doing a lot of aerial spraying and it comes down upon us, into the ground water and the soil..do some research and see .You can ask for a heavy metals test to see what toxins you have absorbed ..I have been having similar ..
Have you seen a neurologist, opthamologist, or even better, a neuro opthamologist? The lightheadedness could be a result of your brain's reaction to the blurred vision. The eyes are basically an extension of the brain and a neurology visit might be helpful.
Has anyone checked your fasting blood sugar? It sounds like high or low blood sugar. Are you on any meds that could cause these symptoms? Do you have any other symptoms?