Hi, I'm new to the boards and I have a question about something that's been bugging me.

Often times when I'm sitting down, or just any time, I'll get up, and experience blurred vision and extreme lightheadedness for about 5, long seconds.

Does anyone know what this is? I'm guessing it's either blood rushing to the head or something but again the feeling of lightheadedness and the blurred vision is intense.

It's called orthostatic hypotension. You can look it up.