Do you think I need a new engine?

Mazda 6 2011, diesel 2.2L

I was driving when my cars red oil pressure light came on, soon after then engine stopped and I was stuck in a roundabout, managed to get it started and running for long enough to get off the roundabout then died again, now won't turn over at all.

Is the engine f**cked?

If so, is it usually worth replacing or just getting a new car?

Thanks in advance.