I was going to mention the metformin but others beat me too it. I think by lucky they meant the acidosis hadn't got to the life threatening stage.
Sometimes medical professionals don't think.
I had a scan a few weeks back and there was a medical student watching. The radiographer says oh and this is <a long word> , yes it is a tumour, paused for thought then added but its benign. I was thinking excuse me I'm here you know.
At least you are on the road to getting things sorted.