Just a quick question re varicose veins ... I've got some running down backs of legs. Anyway, quite suddenly today I felt a sore lump on back of leg, above knee. One vein was purple and bruised and swollen. The bruising has spread a little and it's sore to the touch and with movement but surface pain rather than 'deep' pain. Anyone know if this sounds like a leaky vein or is it something more sinister (blood clot?) which would require medical attention? TIA.