I'll say go for the career switch but stay in singapore (unless money is not a problem - then go overseas!). there are many options locally such as
SMU's HR grad cert ://.smu.edu.sg/programmes/professional/hrgradcert
NTU MSc Info Studies ://.wkwsci.ntu.edu.sg/ProspectiveStudents/Graduate/MasterofScienceinInformationStudies/Pages/MasterofScienceinInformationStudies.aspx

self study UOL international masters -
://.londoninternational.ac.uk/courses/postgraduate/birkbeck/human-resource-management-msc-postgraduate-diploma
://.londoninternational.ac.uk/courses/postgraduate/birkbeck/organizational-psychology-msc-postgraduate-diploma

how do you know that you will like HR/library/archive work? I worry that you will regret just like you have regretted your degree choice. My suggestion is to go do an internship and get a taste of it before jumping into it. in fact, there are many HR/library/archive work which does not require a relevant degree. have you tried?