First day at the gym, you think everyone is watching. They’re watching their own form in the mirror.

First days in an unfamiliar place come with a feeling of being watched, and a room lined with mirrors concentrates it. Nearly everyone there is occupied with their own count, their own form, their own reflection, and has no attention spare for a stranger. The audience you are picturing is genuinely busy.

Go at a quiet hour if that helps, with one simple thing to do, and leave once it is done. None of this is about how your body ought to look. It is about getting used to a room until it stops being one you dread.