Attending more interviews get you comfortable with the process. I guess the stress is partially due to the fact that you are unemployed?

Ask questions related to work life in the interview. The most you can do is see if the role and manager are then a good fit. Other than that, I would suggest not worrying about this as its out of your control.

If at all there are red flags, start the job search early enough so you could secure your next role without leaving the current role.

Step by step TS, first priority is applying and interviewing. Good luck!