I have petechiae, spontaniously appearing on my thighs and calves, need second medical opinion?

I saw a doctor about petechiae, spontaniously appearing on my thighs and calves, the CBC i got was normal. However my legs continue to be covered with diffrent petechiae. Its been over three weeks that this started, and it comes on in large patches about twice a week, covering about half of my thighs, or all of my calves. Could we be missing something?