That is strange for blood sugar to just plummet out of nowhere. Did you have enough to eat prior to driving in? I know it may sound like a dumb question for someone who's been dependent on insulin for so long, but I've seen similar incidents of accidents caused by apparent hypoglycemia, and the number one issue is usually they didn't eat enough for the insulin to be all accounted for.
It's a good question and one that I was asked by all people I've talked to, and my answer is yes. I had my normal routine morning like I do every single day. Wake up, test blood sugar, adjust with short-acting insulin if needed, use long-acting insulin injection, and then eat a quick breakfast at home. Same doseage, same everything. Today, I did the test and the blood sugar was fine. I still ate anyway without injecting anything additional and went on my way. The ONLY difference today was that I was up an hour earlier than normal as I had an early morning teleconference.
I went to the ER at the hospital to get checked out since as the day went on I was feeling more and more uncomfortable. I went and checked in, and the physician there asked how it happened and what hurts. They then did the routine vitals signs and inspections and saw that all the bruises and marks on my skin were indicitive of where the seat belt was worn. So although the seatbelt left some marks, the windshield would have left far worse marks. They did a chest x-ray and it was kind of cool being able to look at the film and see everything looked fine before the doctor even saw it. (The x-ray technician saw where I worked and asked if I wanted to see the images since he figured I'd enjoy it. I did!) The doctor came in and said that the x-rays looked just as they should for someone my age, and although there were some discolorations in the area that was hurting me, it was probably just a bruise. If I wanted an MRI, I could have one but it would make no difference in the treatment he was going to prescribe.
So he prescribed a bunch of blood work to see exactly what is going on in my body and ensure there are no liver/adrenal/kidney problems which can result in odd blood sugar drops.
He also gave me some Naproxyn pills to control the inflammation, and a LOT of modertely powered Vicodin. I'm almost tempted to just advil the pain and deal with it for as long as I can so I can enjoy my Vicodin, but I'll be a good boy and not do that.

So the doctors confirmed that there's nothing really wrong with me and that I should be fine. No massive injuries aside from the standard bumps and bruises you would expect to see after a car accident.
I've had bumps and whatnot in my car before, but this was my first real "accident" where the car was basically trashed and the airbags deployed. I'm still a little stunned and not looking forward to how I'll feel tomorrow. I've still got to go to work, but it will be a bit rough. Then I have to go to the shop and get all my stuff out of my wrecked car and see what the insurance company decides. Depending on what they decide, I may be able to get a VERY low mileage car from my auto dealership for a monthly price of next to nothing. (As I alway have a bolus of finances available to cover for emergencies, and I had been saving up to build a patio in my back yard).
So I'm better, a little bit sore.............. okay, VERY sore but happy that my CP is done and working and that it hooks up to my laptop and my laptop hooks up to my TV. Donkey Kong will help ease my pain.
