My 1 year drank coffee should I worry

I left my coffee out which I normally never do, it was from four hours previous.

I went to clean some thing and turned my back for a quick second and he had already gulped a big portion of black coffee back. I only saw him take one swallow, but by the look on his face it looked like he got a lot more.

Freaking out not sure if I should be worrying or not?

I’m just flushing him out with water at the moment.