4 days after a filiing in molar the gum has gone white at that tooth. Gum all the way up to the front teeth has become rough and discolored. Painful?

Very unusual. Sorry to hear that you're in pain and dealing with a swollen gums. Call your dentist to schedule a re-evaluation. Small adjustments can make a big difference. Take care.
Dentist. It sounds like you have an infection. You likely need XRs, antibiotics and something for pain. All the best and feel better soon.