This is very close to heart, let me share my personal experience.
I joined a new job and found it extremely hard to cope. A new city, a taxing role, and got hit by anxiety.
I didn't want to tell my manager because I would look weak. But after a point, it became bad. I would have to walk out of meeting rooms because of cold sweats and high heart rate.
I ultimately told my manager, cuz it looks almost like I'm a casual college student.
Started the pills, solved it somehow in 2 weeks (under). Never happened again. But for those 2 weeks, I was relieved I told them. It just made the anxiety lesser too, cuz I knew they knew.