Weird medical issues?

So lately I've been having some issues which I believe to be connected to my health. It's really weird. I was with my dad at an installation he was being installed at and I almost passed out. It's the weirdest feeling ever. My heart started racing, my ears started to ring, I started to sweat, my head was pounding, I started to get weak, my vision went white and I almost passed out. It was when I was standing at the beginning of the ceremony and then every time I stood after that it would start to come back. Now those of you that know me know I don't like being the center of attention so it would have been awful to go down, but I'm sure I was that close.

The reasoning behind it remains a mystery. I am prone to panic attacks when I get stressed and/or nervous, but I didn't feel stressed or nervous. I was my normal self, taking pictures for my dad, enjoying an evening with my family. Now for the past few days (since that day) I seem to be getting dizzy more often and have no idea why. I'm hoping it's not something serious. I have a clean bill of health for my heart, but it could be my blood pressure or blood sugar or something like that...who knows.

All I know is it's making me pretty nervous, especially if this begins to happen more regularly. Maybe the panic attacks I got as a teenager are getting worse. That would not be good. Any thoughts and/or suggestions? Anyone ever experience similar situations or symptoms?