Even a severe sunburn does not have so much pain after 7 days. I strongly suspect you may have a secondary infection of the sunburn and this may be getting deeper causing cellulitis. I would treat a patient like you with a 5 day course of an oral antibiotic like Augmentin or Dicloxacillin along with a short tapering course of oral steroids for the inflammation. Till you can see your doctor I would recommend vinegar compresses on the affected area - thrice a day- followed by neosporin cream. Also take Tablet Advil 400 mg three times a day after meals. Both of these are available over the counter without a prescription. Needless to say get as much rest as possible and keep your legs protected from sunlight.

For the compresses: mix half a cup of white vinegar in one liter of tepid water, soak clean cotton or gauze in it and leave over the affected area for 5 minutes and then gently wipe clean. Store the mixture in the refrigerator when not in use.

Please feel free to ask if you have any queries.

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