Got a job back in September and I’m not sure if it’s the right fit. Should I look for another job?

So it’s been 3 months since I got this job and last Friday I had a 1:1 with my boss and she said that it looks like they wanted someone senior for this role and not someone who is still developing their skills. She said that I’m very slow and I haven’t been able to deliver any project yet.

I mean I just joined the company and I’m still learning about different data warehouses we have and the way company’s data is structured. She said that it’s not fair of me to ask for more flexibility and I need to give it a thought if I can work here cuz the CEO said that there is no learning curve in this company and we want people who can deliver results faster.

She said that 3 months into this and she thinks that she should’ve hired a more senior person. Now, I’m not sure what to do. I don’t like this company at all, ever since I started working here, I’ve felt depressed. There is no positive reinforcement here. They will not appreciate the amount of effort you’re putting in. I’m constantly overworked. I worked on thanksgiving too, and work till 10 or 11 pm. 9 AM - 10 or 11 pm almost everyday. My mental health has declined, and I’m not sure if this is the right fit.