Consult your doctor or maybe try the ask a nurse line. But definitely let your physician know what you're going through.
Its moat likely the blood pressure changes going on in your body but if it is really concerning you call the dr. Or if they arent there call the hospital for advice.
It could be hypoglycemia. I've been getting bad low blood sugar attacks almost every day and I almost get to the point of passing out. I would ask your doctor. Do you have any symptoms before it happens that let's you know it's about to? Hypoglycemia causes sweating, shakiness, disorientation, severe hunger and weakness. If you do get those symptoms beforehand, try eating some candy. I have to carry it with me everywhere now.
Having one right now. 6 wks. I feel like I'm not me and if I get unfocused I just feel lost.. So fricken weird