Skin irritation like pricking of pins.

Hi Doctor, I’m 19 and my problem seems to be very serious. I experience skin irritation and itching during some activities like cough. Whenever i cough, i feel itchiness on my body and it feels like pricking of pins in the skin. When I perform  exercises ,I used to do handstand but now it's next to impossible this has resisted my workout. I am unable to do anything which requires force holding breath like cough,strong push, handstand, pushup, running etc.  my whole body starts itching. I cannot even bear woolen material on my body, in winters too i wear cotton wears. Earlier it used to happen only on mt neck but now it’s spreading to back, neck, head, arms, legs, feet, almost in the whole body. I used to experience this an year before too but it was very minor till then but since a month I’m not able to do anything with it. Whenever it happens, i gotta remove my clothes and rub my body with a cold cloth. I cannot walk properly on a road.my body gets heated and it gets out of control .