If a leg has changed suddenly, this page is not the place for it. A sudden change in one leg needs a clinician, not a form on a blog.
If your question can wait, this page has a form for a non-urgent question or for a guidance source you would like compared with another. Messages sent through it are not delivered, so keep a copy of your question and take it to a clinician.
Before you write anything down, check how the main sources describe your question. MedlinePlus on varicose veins and spider veins and this overview of venous disease are good starting points.
You can also compare how professional and public bodies word the same condition. The page on varicose veins from vascular surgeons and a page on symptoms, causes and treatment are two to start with.