You seem to be suffering from phlebitis.
Phlebitis is a condition in which a vein becomes inflamed. The inflammation may cause pain and swelling. When the inflammation is caused by a blood clot or thrombus
, it is called thrombophlebitis
. Thrombophlebitis usually occurs in leg veins, but it may also affect the veins in the arms.
There are two sets of veins in the arms and legs, 1) the superficial veins that run just under the skin, and 2) the deep veins.
In your case it seems to be the involvement of only superficial vein of the arm.
affects veins on the skin surface. The condition is rarely serious and usually resolves with local treatment of the inflammation.
If the doctor makes the diagnosis of superficial phlebitis, the treatment includes warm compresses and anti-inflammatory medications such as ibuprofen
If there is a skin infection
associated with the superficial phlebitis, antibiotics may be prescribed.