I had an exploiting offer without an interview and then I asked for a interview with the hiring manager. Do I still have to wait for HR to call or do I call them?

So, a couple of weeks ago I had an exploiting offer without an interview. They instantly were like "You're hired!" and they gave me 48 hours to make a decision. I didn't even speak to the manager.

After the 48 hours, I had mentioned to them that I didn't think I wanted to move forward with the process because speaking to the maanger was important to me. They are desperate for people it seems (I'm a new nurse, so this is at a hospital) and accomadated and then eventually set me up to have an interview with the hiring manager and it ended up being a couple of weeks later.

Now, I'm not the best at interviews but I thought I did OK with the manager yesterday. Since I already had this previous offer but requested to have an interview, does HR need to call me to ask me about my decision or do I need to call them first after the interview? How much longer should I wait to call them if I am still waiting to hear back from others?