My work Z type expires on 17. February and I want to spend five days in Beijing.

I bought flight ticket to my country (23. February) and I paid hostel for five days in Beijing. I'm going tomorrow to PSB because I hope they will expand my visa from 17. February to 23. What do you think, will I have a problem and how to solve it? The main problem is very bad HR in my company...they didn't tell me nothing about my Z type, what should I do after my work permit expired...