Manager gave me a warning to improve otherwise they'll let me go, should I start looking for another job? What do I do?

To summarize, this is my first job working at a restaurant, I struggle with anxiety and I'm working slower than some of my other co workers, today my manger contacted me saying other workers including my manager noticed I'm not getting the hang of things, and if I don't improve within the next one or two weeks, I'll unfortunately have to be let go.

I don't know if this is a roundabout way of saying to get ready to move on or if my manager genuinely wants to see me improve, I'd appreciate any advice anyone can give me ):