Dizzy for no reason.

Amanda • Mon, May 23

Ever since I woke up this morning at 930 I've been extremely dizzy for no reason. But I only feel dizzy when I'm sitting up or standing up. I have never been dizzy for this long. It is almost 130 and I have no idea why I'm dizzy. Any ideas out there? When should I seek medical attention? I'm not pregnant (as far as I know)