To be a dermatologist, you do have to go to medical school and it's one of the most competitive field there right now because of the life style. If you are interested in skin and skincare, you could look to be trained as an aesthetician. Or you could try to go to nursing school and maybe try for a nurse practioner and then work at a dermatology office.
On another note, I don't think age should hold you back about medical school. There was a wide variety of ages in my med school class. And you wouldn't believe the spectrum of ages I have seen during residency. So if that's what you really are aiming for, you should definitely go for it!
