What is gym anxiety?
Gym anxiety is the dread of being watched, judged or shown up in a gym, and it stops a lot of people from starting at all. It usually attaches to specific moments: walking in, not knowing where to stand, using a machine for the first time, or feeling that everyone else knows what they are doing. Those moments are practical problems, and practical answers remove most of them.
If anxiety is affecting your life beyond the gym, or does not ease, talk to your GP. A personal trainer can make the gym easier to walk into; they are not the right person for anxiety itself.