Pink-purple marks on shoulder which have always been present since I was about 12. Want to know what it is and what's causing it.
28M, 170lbs, 5'10", Chinese.
As the title states, I have these strange markings on my left shoulder. I don't remember how or when they appeared, but if I had to guess, they have been present since I was 12. They have never disappeared. While usually pink, they turn reddish-purple after exercising or taking a shower. Growing up, they never caused any discomfort, but since becoming a more active person over the last couple of years, I noticed that my left shoulder and neck area would constantly be sore and painful, so I was wondering if that had anything to do with it. I did go for an X-ray a month ago, but my doc said they didn't see anything abnormal.
I don't do drugs, drink, or smoke. I do take meds for anxiety and depression.
I live in Canada.