It sounds like your blood sugar levels might be off. Try drinking some apple juice and lay down if you think your levels may be low. If nothing helps, I would call your doctor :) I hope you feel better!!!
I'd call my doctor if I was you. What's your typical blood pressure? You may have a low blood pressure but that doesn't mean it can't go any lower. Just depends on what is normal for you personally. Do you have problems with your sugar levels? Are you hydrated?