Should I quit my job?

I’ve been working at a certain grocery store for a month now as a part timer and ever since I’ve been working here, I’ve been getting sick constantly and in pain. For context, I work in the dairy department where I’m pretty much in the cooler most of the time. They didn’t provide me with a proper uniform for the cooler but gave me a regular thin long sleeve shirt instead. I was told that I’d be working mainly day time as per when they asked me my available hours but they recently put me on closing shift for a week without informing me why. I was also told that I would be working every other day and I’ve been working back to back days (4 days in a row). To this day I don’t have a employee number to punch in and out or to indicate when I take my lunch or breaks. My first day pay is also being withheld from me until the day I quit which I don’t understand either. I haven’t signed any union forms nor done any health and safety requirements nor even had a orientation. They also expect me to do “facing” for two departments on my own. It’s basically a job that requires more than two people in a department but has sometimes 2 people working even only 1.