Hi there ~
The purple rash
might just be a contusion
for having worked out strenuously in the area. Observe it like you did with your previous lesion and see if things improve. If they do not, please visit with a doctor who can run some blood tests to find out if you have a blood abnormality like a low platelet count
or other, which is making you more vulnerable for easy bruising. I hope this helps.
Take care and have a lovely day1