when i get hit by anything , whether it be by the pc desk or by a box or by my bracelet when i walk. sometimes i get lots of small bumpy circles together and something like if a something hit me in a sliding pattern in my hand
i get a big all connected bump which is really embarrassing. i mostly get them in the part of my arm where there is no hair the bottom part of my arms ( sorry don't know actual name ) also near my hands
and is caused by hyperactive immune protective mechanism.
However, this may also be a blister and there are several causes of blisters.
'Blisters are usually caused by injury to the skin from heat or from friction, which create a tear between the epidermis—the upper layer of the skin—and the layers beneath.
Short periods of intense rubbing can cause a blister, but any rubbing of the skin at all can cause a blister if it is continued for long enough.
Sometimes, the skin can blister when it comes into contact with a cosmetic, detergent, solvent or other chemical; this is known as contact dermatitis. This may also need to be ruled out.
It would be best to consult a doctor if it does not resolve on its own in a few days. Anti-allergics prescribed by a doctor may also be helpful.
i been having it for 4 years or so what ever hits my skin makes those rashes for example i work with boxes right so if 1 of them just hits me and rubs on my skin ,even if it is only for 1 sec of hitting/rubbing a rash will appear and sometimes it burns