I developed a kind of allergy in December.
When i'm cold, slight inflammation erupt from my skin and it itches like mad. The more i scratch it, the more the swelling extends to other areas of my skin.
It looks like mosquio bite. i was told by a trado-herbalist that it is a symptom of impending fatness. Please doctors in the house, Help!

no its not a sign of impending fatness. Stretch marks/ varicoe veins are.

You neet to go get checked as it may be some sort of worm that's living just underneath your skin. It may be a virus. My friend used to have something like that. When she itches it spreads and it got the point that it caused sores and was very unsightly.

i dont think its a sign of gaining weight or grower fatter.it might be lichen planus,atopic dermatitis, a hypersensitivity reaction or even a viral or bacterial infection.
go see a dermatologist for the right diagnosis and treatment.