Working at L3onf@st.sdn bhd

I graduated with a diploma in mechanical engineering, not to boost myself, because nowadays diploma is also not very high qualification and I dropout during pursuing my degree. So my story begins in February which is after CNY I started working till now. The job scope I applied for is business coordinator in a warehouse. So after I got in I have been given a 3 months probation. So here is how it goes. I started with stock checking, then picking items. And I am not talking about small items, The items I deal with is big and heavy like toilet bowl and basin, but also got small items. The job description is about handling orders and dealing with customer. But it gets worst.

The manager ask me to lift heavy things, then sweep floor(the whole warehouse), then when I go back on time, the manager ask "why go back so early? got wife waiting ar?" Then like to change from A to B. Ask u do A then after done she will said I ask u do B la.. When in good mood c u time hehehe when bad mood, she will said what r u doing?? If can't finish u don't go bek today!!!. Or worst ask me change her pet tortoise water and then ask me to crush tin cans. Sometimes work so tired picking things walking here and there,up and down then at the end of the day only get a packet of Kopi ais. She think she can buy me with just a packet of kopi asi.
Then the office ppl also treat me as their handyman, when need to bring things to their car, they will call me like sometimes I just pass by them they will stop and ask "hey help me take this to my car or hey help me find some unused box" I mean cmon I am a diploma graduate. I didn't sign up for all of these. When confirm time which is June the Hr said I mayb can start doing some paper work but at the end just kuli till now.. Seems like I have been fooled, The worker(warehhouse dept) there also half half la, some ok some show face and backstab.

I really can't tahan anymore, I work till spinal bone pain and leg muscle pain, Hand got a few scars since I got in there all because I doing the manual labor. Shud I just leave? every single day once I open my eyes I just thinking of leaving. Am I a weak person because work not even 1 year, just 8 months. Or is it the job got problem?

Thanks guys for all the advice. I work till the end of this month. Gave a resignation letter to them already. Can't wait for freedom.