I had a condition called vaso-vagal while pregnant. It was the worst thing as I couldn't get a handle on it. It started by seeing while dots and then my heart would race and I would be short of breath. Anyway, it was due to low blood pressure (but not out of range, just low on the scale). My internist called it classic fainting. I resolved the issue by increasing my water intake, increasing my protein (substantially) and increasing my salt. Essentially, I ate a lot of peanuts and PB & J's. After a month, I got it under control. I hope that this isn't what you have, but if it is, it is easily controlled once you know the problem. Take care of it. It wasn't harmful to the baby, just very stressful for me.