I want to quit...

Hello... I am 15 years old and I have dermatillomania. I constantly pick at my arms and sometimes my legs. I do it hoping for perfection but the end result is worse than before I picked at it. I am constantly questioned about what is wrong with me and why my arms look like they do so I always try to cover it up by wearing long sleeves, wristbands, bandaids, etc. I deny that I do it when people ask but I don't know why. I want to be able to wear short sleeves again without people asking me a bunch of questions about my skin. If anyone knows what this is like or can help me or even just give me advice that would be great. Thank you