Hard,swollen cord/rope-like vein (i think great saphenous vein)along whole leg. can only go to gp in 2 days.so terrified of dvt/other serious problem?

Superficial clot.: What you describe sounds like a clotted greater saphenous vein. This would present as a palpable cord along anywhere from the medial ankle to the upper thigh. This is called superficial phlebitis but there is always a chance that this can extend into the deep system to cause DVT. You should have a venous ultrasound and see a vein specialist as soon as possible or go to the ER for evaluation.