Red and itchy leg also now blistering?

Blistering leg: You may have a staph infection caused by scratching and abraiding your skin. Consult your doctor immediately.

Blistering rash: Blisters with redness and itch can signify a contact dermatitis such as poison ivy or oak or sumac if indeed you have had exposure to weeds or vines outdoors. I would suggest white vinegar soaks and apply Hydrocortisone cream 2-3x/day. If the condition worsens, please see a dermatologist.