Why didn’t I get paid??

I’m working at a little family owned restaurant for cash I started last Thursday 11-11 and he pays on Sunday which would have been 11-14 I mad 300$ he wrote the check but said he keeps it as a deposit & I’ll be getting paid a week behind. So I’m assuming this Sunday I’ll be getting the $300?? Or he said he’ll give me the $300 on 11-14 the day we’re talking about it but this week working I’m not gonna get a check..? So I told him not stay with the 300$ as a “deposit”… Like wth why is he even doing that? Why not just pay me for the week I worked that week I’m not understanding I feel like i just worked for free…