A While Back I Had A Pretty Large Almost Perfectly

A while back I had a pretty large almost perfectly round red spot that eventually turned purple and even later, about 2 wks., had formed a dry skin patch over it as if it was bruised and burnt. That is how it felt too. Tender but as if it were raw skin. After about 2 weeks almost 3/4 weeks to fully go away..its been about 2 months and now it has returned..