Sorry to frighten you.
I'd do some investigating for sure.
I think my crank failure was realistically avoidable. There was warning signs, I figured it was ok coz it still ran good once going. I don't think my head gasket was an instant failure, it happened over a period of at least days, if...
How is it stalling out? Kind of sputtering to a stop, or a hard stop?
If it's a hard stop, pull plugs immediately and check condition.
Are they wet? Wet with fuel, or wet with coolant?
When my head gasket went, it did what you're describing, but the stumble quickly became a total stall out and...