Is this considered unpaid labour? Or just a part of working as an adult?

hi i am a poly grad working part time at a clinic before uni.

clinic working hours, and my own stated working hours, are 9am-6pm. I am paid for the time i work there, from 9am-6pm.

boss requires we come in 20-30min early to set up clinic and prep for patient. I kena scolded once for coming in only 20min early. boss expects us to come early for work, and even earlier if the previous day’s work was not finished

boss frequently schedules patient all the way till 6. last patient leaves either around end of 5pm or 6pm+ish then the part timers need to clean up and close clinic after that, and some issue to discuss or what not

so end up finish at 6.30pm. boss starts ushering us out, telling us to come early next day since some things are not done and it’s 6.30pm already.

so in reality, actual working hours are 8.30pm-6.30pm. an extra hour more. Sian.

it wasn’t a thing when i first started working lah, but i heard from new hires they have a 2-4 week no pay training period. boss honestly quite rude (yelling and swearing), saw this new girl cry before. ok but i thick skin so no issue, but feel like abit harsh leh. especially since i think the girl quite obviously has some kind of autism (but the smart kind lah). but boss not discriminatory, yell and swear at everyone equally LOL

boss only hires part timers, most are poly grads like me waiting for uni. pays quite bad, but can still tahan cuz paid in experience HAHA. $8/hr after cpf

is this the normal working experience? feels damn sian working LOLZ cant imagine this is adult life, bleak sia