Leaving a new job after a week

Any guidance would be appreciated.

Work in higher education, just started in a new office. Previous office was ok, was there for over 2 years, oversaw my own programming, had a team of student workers that were great, 50% WFH, very quiet office. My relationship with my supervisor wasn’t the greatest, but we made things work & they would generally leave me alone unless they really needed something. Long story short, I got passed up for a promotion & left the office for greener pastures.

The new higher level position I am in now in this new office is way more hectic. Way less WFH time, way more responsibilities, way more traffic in the office. I’ve only had less than a week of training, & am now expected to carry out my duties on my own & I have been super overwhelmed - usual timeline for training is about 3-6 months, but it’s their busiest season & the office is slammed. The team is nice and my supervisor seems confident in me of course, but it has not helped me settle in at all. It’s only been a week but I haven’t been happy at all since I started. I’ve been super anxious everyday, to the point where I’ve been waking up out my sleep in the middle of the night to ruminate, & then crying before leaving the house to go in. But, because this is their busy season, they expected me to hit the ground running & hope to fully train me in a few months.

Today I panicked & went back to my old office and broke down crying in my old supervisors office. Told them that I missed doing programming, didn’t think I was a good fit for where I am now, & asked if my old position was still open. They said my position was to be eliminated, but they would advocate about bringing me back if I was really interested, & would see about giving me an extra responsibility that I had advocated for before leaving.

After sitting & thinking about it, I don’t know what to do now. I do feel a bit of relief after having that talk with them. I’m probably jumping the gun as I don’t have another offer right now, but I really don’t want to burn a bridge with this new office because they have been really nice. After thinking about it all day though, I know deep down that I am not a good fit for this right now. People that I have confided in have told me no job is ever worth your mental health, & I feel now that losing the flexibility probably wasn’t worth it in the long run for how my life is structured. I have to do what’s best for me, right?