Quick 2 day trip to Shanghai

Hi, we are doing a quick visit to Shanghai from Perth, Australia.
We are flying in on a Monday night 8pm: Perth - HK (2hrs in transit) then HK - Shanghai.
Tues / Wed in Shanghai then fly back out Thursday morning - same route / transit thru HK on way back.

From what I have read I don't think we qualify for the 72hr free transit?
We will have to apply for a visa before we leave home I think?
Thank you