Hi Globerunner
Yep, I did the "secret smoker" thing too. After I had given up initially, I started again but was too proud to tell my family I had re-started. Bit thickheaded as they were all smokers anyway and wouldn't have noticed the smell of smoke but pride's a funny old thing.
Anyway when I finally gave up (which was fun because I couldn't confide in anyone! :evil: ) I had all the symptoms you mentioned especaiily the dizziness, palpitations and tiredness, so much so that I wondered if it was all worth the effort!
I would hazard a guess that it is due to the increased oxygen getting to where it needs to be, having lungs that really do breathe deeply..I think the tiredness is part of that. I very much doubt that any of it is caused by low bg's.
It is what our bodies are supposed to do, to regulate us naturally and we screw that natural process up by inhaling the equivalent of glue.:sick:
My side effects (physical ones) too a good 3 months to start to clear but it honestly is worth it in the end. Get yourself as much help as you can be it patches, potions whatever and we can give you support here. Good luck.