Okay, I need some help here...

For the last few weeks, occasionally when I stand and start walking, I suddenly feel tingling down my arms and across the back of my neck at the base. Then the tingling also starts at the top/temples of my head. Then I start to feel light headed. I race to sit down, and I get kind of short of breath, but I make sure to breath slowly so I don't hyperventilate. I almost fell down the stairs this morning, but had the smarts to sit down as soon as I felt it come on. It couldn't have been low blood sugar; I'd just had an egg.

I don't know if this is MS related, or if it's cardiac, or if the pcp should handle it. So I haven't called anyone.

Any ideas, friends?