I think i have an arm thrombosis, what should i do?

Go to the ER: Its not clear why you think there's a blood clot in your arm so an accurate diagnosis is the first step. If you indeed have a deep vein thrombosis (DVT) it is a life threatening condition since a clot could break free and travel to your lungs There is no home remedy for this but spontaneous DVT of the upper extremity is relatively unusual. Nevertheless, if its a possibility you belong in the ER.

Agree with Dr. Z: If you think that veins or arteries in the arm have a blood clot, it should be treated with urgency and you should go to the emergency/casualty department of the nearest hospital. Wish you good health!