my watch is RUNNING BEHIND?

Please imagine a context when I dramatically realize that my watch isn’t keeping accurate time.
So Can I say:’‘my watch is running behind’’,or it must be anything different ?
Is that the most popular way of speaking.

Hi duc

I’d say the most common expression is “My watch is slow.”

Or you can also say:
my watch gains 20 minutes a week
her watch loses 5 minutes daily