hello katie.
yes, you should be concerned. but there are absolutely no hurry or worry. it may be a developing varicose vein. there are few diagnostic (postural) tests which a physician has to do to locate the cause. i have seen many patients who lives with varicose vein for years and years together without any treatment or major symptoms. or in some case your vein may be temporary and may go off itself (if due to temporary internal pressure ). you can consult a chiropractor for regular exercise ones u are diagnosed.