I have a negative symbol tattooed on myself. No one has ever seen it but my husband.
Why has nobody seen this tattoo?
I keep it hidden so I don't have to explain things.
You are allowed to put anything you want on your body but negative symbols will make people think that you believe those negative symbols. People might see them by accident or if you have to go to a hospital.
OK
If you feel embarrassed about it you can try to get it removed or covered up. Everyone grows as a person and no longer believe the things they once did and that is a great thing. Maybe be more careful of the symbols you use on your person.