Hi Jesben,
Like Sue says, we are not really qualified to give this kind of advice, so definately go and see the Dr. I hope you are feeling better by the way!
To be honest, what you describe sounds like too little sugar, rather than too much...but if you are type 2, and aren't taking anything for it, then this is very unlikely. Just to share experiences, when my bllod sugar is high I generally feel awful. Dry mouthed, thick headed tired etc. I have never fainted though.....and never, ever managed to do so in an elegant fashion!
The only practical thing I can suggest is either nagging teh Dr/nurse to give you a blood glucose monitor, so if you feel like this again, you can do a quick check and find out what the situation is. If you are still feeling rough, and can't get an appointment for a few days, you can buy them quite cheaply from the chemists...but check that you get one that has a few test strips free with it, or it will be no good. Not an ideal solution, but for £20, might be worth teh piece of mind.
Good luck!