Hello. Welcome to ask the doctor.
I understand your concern.
I have seen the attached pic also.
As per details, the most likely possibility for your rash is Purpuric rash.
It may be due to sudden spontaneous trauma leading to rupture of cutaneous blood vessels and collection of blood beneath skin.
Other causes include coagulation disorders, platelet dysfunction, decreased platelet count etc.
Get yout Blood sugar levels, platelet count , Bleeding time and Coagulation time done.
Visit your doctor so that he can do examination of the rash and order the test for you.
You can share my opinion with him.
I hope it helps.
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