Secondly, there are lots of views already on this thread. At the end of the day you have to take it on board and then decide whats best for you and your baby.
HK employment laws are really really crap, but one area where they are very clear is what happens to a lady while pregnant. Basically you employer cannot touch you. Please take that into comfort when deciding your next step.
Can I ask, will the potential father be involved? What about your's and his family? Will you have some sort of support network during and after pregnancy? If you quit your job, what will you do?