Hi, I was diagnosed tonsillitis yesterday. There was rashes within my body but today the rashes become white pimple head around my breast area. Do I have to concern?

Yes I would be concerned and ask my doctor about it. It could be related, it could be something else. Not trying to scare you, but some complications of tonsillitis is rheumatic fever, the symptoms of which include rashes. I got the info here: http://www.nhs.uk/conditions/Tonsillitis/Pages/Introduction.aspx