Here's another good reason to not to be getting too alarmed just yet.
I had a bad dose of dizzyness/vertigo 3 years ago. It started about 2 months after suffering pneumonia and pleurisy so I was putting it down to the side effects of that. But I still went to my doctor; had blood tests, MRI/CT scans, etc. Turns out it was BPPV. The symptoms below describe mine to a 'T'
BPPV is the commonest cause of vertigo. It is Benign as although it can be quite disabling, it is not due to serious disease; Paroxysmal because it occurs in short bursts of up to one minute; Positional as it is provoked specifically by movement to or from certain positions; Vertigo – dizziness defined as an illusion of movement.
Symptoms of BPPV
The vertigo is generally rotational (like getting off a roundabout) but sometimes sufferers, on lying down, will feel that they are falling through the bottom of the bed or, on getting up, that they are being thrown back onto it. The classic provoking movements to induce BPPV are: lying flat, sitting up from lying flat; turning over in bed; looking up (e.g. hanging washing) or bending down, especially if also looking to the side. The duration of the vertigo is brief; usually five to 30 seconds but very occasionally lasts up to two minutes.
What causes BPPV?
BPPV is caused when loose chalk crystals get into the wrong part of the inner ear. These microscopic crystals should be embedded in a lump of jelly. The crystals weigh the jelly down and make that part of the ear sensitive to gravity. The crystals are constantly being re-absorbed and re-formed and over time fragments come loose. Lying flat can then occasionally cause some of the loose debris to fall into one of the semi-circular canals; the parts of the ear responsible for sensing rotation. Movement in the plane of the affected canal causes the crystals to move along the canal, stimulating it and giving the sensation of rotation.
How is BPPV treated?
At least a half of all cases will get better without treatment though this may take months. As BPPV is basically a mechanical disorder, drugs have no effect and should be avoided. Most cases that do not resolve rapidly can now be relieved by the appropriate Particle Repositioning Manoeuvre; of which the most commonly performed is the
Epley manoeuvre which offers instant relief of symptoms in nine out of 10 patients.
http://www.menieres.org.uk/information-and-support/symptoms-and-conditions/bppv
There wasn't anything really that the doctors could do other than the Epley manoeuvre, but it did wear off over the coming 6 months or so. Now I only get the one minuet spell when I first lay down each night on my right side, lasts seconds and that's it. Very occasionally I'll get it in the day time now, maybe when I bend down to tie a shoe lace or something but I've not studied what could have brought it on anymore.
It's winter, have you had a bad dose of the cold just recently which might possibly have triggered this? My mother-in-law has had it 18months ago and it was not long after a severe head cold. As the medical profession don't know that much about it yet and it's triggers, it's just my thinking that such things as head colds/pneumonia could be triggers. And, like mine, hers wore off over a matter of months and rarely has any residual spells of dizziness. She's not T2 but does have blood pressure/cholesterol meds.
Might help with your doctor's diagnosis if you kept a record of those spells/what you were doing at the time they occur, how you feel when you lay down at night on your right or left side, etc.
I was diagnosed with T2 a year ago, I'm on 1 x 1.25mg Ramapril for blood pressure, 4 x 500mg Metformin,
1 x 20mg Atorvastatin. None of these have affected my BPPV; still only have that one small dizzy spell when I lay down on my right and the rare occasional one maybe in day time. But the I also go to an osteopath, every 2 months, who works on my arthritis in the hip and disc trouble in the upper back and my BPPV manoeuvres

I think that helps a lot

Oh, and the weight just melted off me from day one of starting on Metformin, I've lost one and a half stone in the past 11 months, don't really want to lose any more but my doctor wants another half stone off

My dietician at the time said doctors are obsessed with wanting their diabetes patients right in the middle of their normal weight on the BMI chart. It's not going to happen.
Link to information has been added by Moderator.