Erratic Levels

I currently take 2 x Metformin, 3 x daily and everything seemed to be fine until just before Christmas. My BG levels are now all over the place and it doesn't seem to matter what I eat. I had no sugar and it went into the 20s, I tried eating some sweets the next day and it was around 9ish. I was on gliclazide for a while last year but it made my BG levels too low. I have an appointment next week with the nurse but wondered if anyone else had experienced this?

It started about 4 days before Christmas, I tried being very careful what I ate one day to see if it came down, avoiding the thing we know are not good. Strange thing was my BG was in the 16-18 range. The next day out of pure curiosity I ate things I shouldn't, sweets, cake and white bread etc. That day it was in the 8-11 range :? . When I wake up in the morning it can be 16 yet 2 hours after eating lunch it can be 8. Also I have been getting very sharp pains in my toes and also a numbness, it might not be related due to having fibromyalgia. I am more lethergic than ever and my head feels 'woolly', like brain fog (more than it does normally with my meds). I don't eat a lot as I can't do exercise due to the constant pain etc of my other ailments. I don't drink alcohol or smoke and normally my BG levels are not higher the 12ish and settle ok. I suppose I'll have to wait till Tuesday and speak to the nurse, my doctors are not that helpful so I couldn't speak to anyone this week.

This is mad, if I consume sugar my BG level is going down.