Update....
I had one last go at starting it, no go, so I whacked the steering wheel hard, and it freed up.so on my way to work I phone BMW assist and asked if they could come and check it out at work, I was told no, as I'd managed to get it going they wouldn't until it failed again, let's hope it doesn't.
In the 31 years I've been driving, it's been the first time a car has let me down on a work day, and I've owned some right shed in the past