Starting problem

My L322 2004 4.4 after running perfectly suddenly developed a slight whining noise after starting up.With a 3 mile journey home , I wasn't unduly alarmed and decided to investigate when I got home.After listening to the engine with the bonnet up on tick over, I decided to switch the engine off with a view to calling the garage tomorrow. However,when icame to restart the engine,there is a unhealthy grinding noise and and I turned the ignition off without the engine starting.The weather conditions are extremely cold and I'm thinking there could be issues with the starter motor, I'm thinking something sticking maybe?Anybody any thoughts?

Starter motor stuck in mesh?

That's my train of thought too.Although I've removed innumerable started motors ,how big a job is it on one of these?.

Is easy enough as long as you have a long enough extension for hex bolt

Thanks for that!