Lately, I have been regularly experiencing dizzy spells upon standing up. A few times I thought I would black out. I figured I was standing too fast or it was just a random blood pressure drop. Today i experienced, while sitting at my desk at work, the feeling of dizziness like I was in a falling elevator and I was disoriented, grabbed the desk cause it felt like I was falling and needed to hold on. I have been eating healthy, drinking plenty of fluids, getting regular exercise and sleep. Was not experiencing anxiety or panic or anything. Any suggestions?