Persistent painful swollen vein lower left arm?

Phlebitis Arm: It sounds as if you have developed superficial thrombophlebitis of a vein in your arm. You should see a doctor and get it evaluated, as you could develop bacterial phlebitis which can be serious. Non bacterial phlebitis can often be treated with warm compresses and anti-inflammatories, but you also need to make sure that the phelbitis doesn't extend and cause a deeper more serious clot, i.e. Dvt.

Swollen arm.: A persistently swollen arm needs to be evaluated as to the cause of the swelling. This could be due to a clot in an arm vein or to an inflammatory process or to a mass blocking the venous return. A physical exam followed by a venous duplex ultrasound of the upper arm would be indicated. See a vein specialist or your private physician.