Send a thank you email, thanking them for their time and consideration. Doesn't have to long or overly verbose, but it puts you back on their radar - they'll either say they're still working on the applications, or they'll politely reject you. But 'thank you' emails tend to go a long way after an interview, as it shows you respect the time of the interviewers, blah blah etc.

Keep trying, and consider any "failed" applications as interview practice. It'll be alright, friend, you got this!

I used to interview people. I started with a huge pile of resumes, and whittled it down to a list of "second look". Then that list got reduced to "Interview". I wasn't interviewing people that didn't look good for the role. If you were at that stage, and your interview went well, you had decent odds of getting hired.

I managed all this with a big spreadsheet. I made comments about the candidates after each interview so that I could remember which applicant was which.I would tell people a rough time they'd hear back (if it was "Early in the week", it'd be because I was interviewing candidates until then.

Don't give up hope yet, there are several possible reasons why you haven't heard back. Interviews for other candidates might have been moved/rescheduled. It's possible they're running late for other reasons. It's possible they've offered it to someone else. It's possible someone else turns the role down and you'll still get contacted.

It's too early to tell. But, feel proud that you got to the interview stage. They only interview the people who look good. Interviews are exhausting and take a long time (not just while you're in there with them). Even if you don't get this role, you've learned something and you're obviously doing something right.