Could be an allergic reaction, try to minimize chemicals in your personal products and laundry detergent, fabric softener, dryer sheets. Vitamin C is a natural antihistamine, sometimes you need to take a lot to see results but it's very safe. This is a great site with tons of free info - http://www.doctoryourself.com/ Even if it's eczema, you may find info to help there. Another site is mark's daily apple, many people have shared their results.
I certainly am no doctor but I have read these symptoms can come from wearing colored sox. Many are allergic to the dye in colored sox. Hope this helps.
You could have eczema. Do you have a rash or anything on your legs you could describe? My eczema has been acting up due to dry hot weather. Scratching makes it worse or even if it is a rash or bite it makes those worse too. What does it look like? If it is eczema or a rash you may be allergic to your detergent or something else. Try using fragrance and dye free detergents and other items on your skin. Also, Eucerin , Restoraderm works well to calm down itching. I use a topical steroid for my legs and hands. You have to get this from your doctor. If you get a topical steroid don't get it in your eyes or face.