I hate to break it to you but....
Work IS stress. It doesn't matter what field you're in. Careers are stressful.
When I started at my company, I had no idea what I was in for. Juggling phone calls, fixing printers, doing installs, dealing with pissed off customers disatisfied with the performance of the software, people walking in to my office at any given moment with something new for me to do that I probably didn't know how to do at the time. Being shipped off to random places in BFE America to meet strangers with attitudes and help them set up their businesses and train them....
Very stressful. And yet I've been at it 6 years.
So.....you're becoming an adult now. Being an adult means learning how to deal with stress, and changing when change is required. It's a growth thing. That's not to say you don't know yourself, what works for you and what doesn't.....but this time of transition from college to adulthood IS difficult. It IS stressful. You need to cross the Rubicon as a person and see who you are on the other side.
So TLDR: stick it out for a while. Adapt. Overcome. Grow. Find strength you didn't believe you had in you.
Because I'll be honest......your job sounds very easy to me. Making phone calls and scheduling? Pfffffttttt. (No offense.) I do that on a daily basis, plus tech support, plus customer contacts, plus travel, plus server deployment, plus training, plus eating shit on a regular basis for the failures of my company.
If you'd asked me 6 years ago if I was capable of doing all this, I would have said fuck no. Now? I have more confidence in my ability to rise to the challenge and git gud.
Only you can know you, and what you want to do. But if you think a different job is going to not be stressful, you've got it wrong. Even being a librarian, within the realm of librarians, can be stressful.