Does a person that is experiancing low blood sugar experiance personality changes minutes beforehand?

Yes, can. The symptoms can be different depending on how low your blood sugar level drops. Initially jittery and nervous, then can feel short-tempered, nervous, afraid, or confused. Severe hypoglycemia can cause you to pass out. You could have seizures. It could even cause a coma or death. I have only discussed personality signs/symptoms but there are other signs/symptoms as well. Please discuss with your md.
Frequently. When glucose falls, at some point (usually below 60) there isn't enough to supply the brain and one doesn't think clearly. People frequently describe how they feel differently. Observers can also pick up on changes and should warn the person so glucose can be eaten to stop the low glucose event.