What if the production editor does not respond to important email after a few days? I sent my review of the proof for an article back to the production editor. However, due to the large amount minor corrections I made (roughly 50), I requested a second review. I sent two emails. But now it has already 4 days, and there is no response from the production editor.

I am so nervous because if the typesetter corrects the manuscript inappropriately or even publishes the paper without fully addressing the correction, it would be too late to do any further action.

Can anyone give me some suggestions?
It's been four days, and that might also include a weekend day depending on where in the world the production editor is. Have patience, and let the process work itself out :-)