Veins that size (although small) don't form that quickly. I am sure they were there and they recently got larger. You need a venous Doppler ultrasound done to make sure there is no clots (very low likelihood) and at the same setting they will measure the sizes of these veins and also measure reflux times at several junctions between superficial and deep veins (groin, behind the knee) and also at the level of the leg (perforator veins). At that point they will formulate a treatment plan and do an ablation procedure (if needed) or just perform ultrasound guided or traditional foam sclerotherapy. Seek a board certified vein specialist from the American Board of Venous and Lymphatic Medicine. Check the American College of Phlebology physician locator site. Read the ebook about venous diseases on the link below. I also recommend that you take a supplement like Varicosamin which contains bioflavonods as a preventive measure.