I had blood drawn from my upper forearm for basic testing. For 3days now, the needle site is swollen golfball size, but so is the vein above my wrist?

Arterial puncture? It sounds like the blood was drawn by mistake from an artery instead of a vein. It happens sometimes, especially in persons with hard-to-find veins. Quite a bit of blood can leak from an artery; you can expect bruising in the next 1-2 days. Usually not serious unless pale, cold finger(s) or lots of pain. But tell your doctor, who probably will inform the blood draw personnel; they'll want to know.