Should i go to the er because a boil on my right leg is making it very difficult to walk. so painful. i also am developing red swollen spots on my leg?

Yes: It sounds like you are developing an abscess and possibly cellulitis or deep tissue infection in your leg. You probably need intravenous antibiotics in ER and incision and drainage of the abscess. Please visit the ER as soon as possible.

Yes: I see this frequently in the Emergency Department (ED). It is difficult to advise treatment without actually seeing the lesion, or abscess. I would suggest a trial of warm to hot compresses for 24 hours. If there is no drainage or improvement, then I suggest you seek care in an ED or urgent care.