Need help dealing with stress / when to know if job isn't right for me

I recently joined my bank's ECM (top 3) group in June after doing two years in corporate banking. Needless to say, I've had a tough transition mentally/adjustment to IB. I haven't had any performance issues and get along fine with the members of the team, but have had a few fire-drill incidents on weekends (one which was particularly bad) which I feel have messed with my head. I feel like I'm constantly on edge and unable to relax even when I have down time as I'm always worried if I'm going to get pinged and have to rush back to address something. It's almost as if I fear the future work more than the actual work I get itself. 

I didn't think it was an issue (aka just typical new job stress) until recently when I went golfing with a few buddies on the weekend. I found myself constantly worrying about if something would come up and what I'd have to do. Feel like it's been a constant trend of me worrying about work so much that I'm unable to enjoy myself in my free time. It's also began to mess with my sleep.

I'm fully aware that this type of stress and anxiety isn't probably normal which makes me think that IB just isn't for me. However, I grinded my way to get here (started off in IB Ops, moved cities, than got to the Corporate Bank, then ECM) so part of me doesn't want to give up yet. That being said, I think I underestimated my ability to handle the work/life balance of IB - the Corp Banking hours were around 60-70 a week, so I assumed I'd be able to handle a slight uptick just fine, but I guess I was wrong. I'm beginning to wonder if I should start to apply to other jobs, or maybe even ask my old team for my job back (might be tricky since there are internal guidelines, but would be better than me just quitting the bank)

Was wondering if anyone here had gone through something similarly and had any tips on how to deal with the stress of the unpredicatability of the job? And whether this is a sign that IB just isn't the right career path for me? Fully aware that leaving after a short stint in IB isn't the greatest resume look, but also want to be frank with myself and not drag the job out any longer if I'm just going to be miserable.

any advice is appreciated!