Dazed and confused

I went in for a routine blood test to determine chol and came out with high blood sugar. When I got the results dr put me on meteforim right away. When back for official appt on Dec 26. BS was 282 so she put me on actoplus met 15 mg/850mg. Been testing in the am- 250 but than I get reading like 66 and other reading below 100. I was going to call dr to see if there could be something wrong with meter. I bought a book and it is a sourcebook, I have now read recommendations for books here. The book was positive and had stories from people and how they overcame this. I read stories on here and it just scares me but I know these are the real stories. I still gag when I try to check my blood. I also bought a lot of food for this wk but now I think i purchased the wrong food. Dr gave me 1 piece of paper and it was from drug company on eating. Very little info-now I see that is common among drs. I thought I ws doing good eating cheerios with banana for breakfast with high grain toast. I thought I read to fill with fiber. Sandwich for lunch with same bread. I had a very stressful yr with teen daughter who has mental illness and high stress at work. I think these contributed to my problems. High stress yr for me. I read this evening and kept thinking about things I read and got back up to create a post and hopefully more direction. What does BG mean? I guess I really need to find an education class sooner than later, but will take any advice. Thx in advance.