You need to get yourself a blood pressure cuff and learn to take orthostatic vital signs. Do a search on the internet. Sometimes post stroke light-headedness is from an inability of the body to compensate changes in body position by the brain ordering the blood vessels in the leg to contract, much as a "G" suit squeezes a pilots legs during maneuvers. You need to determine if the compensation is simply delayed or non-existent. Or if the problem is brain related and not due to a sudden reduction in blood pressure due to change in body position. The question is, does the lightheadedness come on suddenly while you are standing, or take place while while you are standing a while. Often it is just delayed, which means when going from a sitting to a standing position you should ensure you have a firm grip on something and do not walk for a period of time. You might also be on a blood control medication that is a calcium channel blocker, which ocasionally causes these symptoms. Have you had a blood work-up and your hematocrit checked lately? This could cause light-headedness. Sometimes a stroke patient is placed on coumadin, which exacerbates hemorhoids. The rectal bleeding can dramatically decrease the red blood cell count in a relatively short period of time.