If the inside of your mouth is always white, you might have a serious yeast infection. I had one too at one point during my EC years. My lips were especially painful and swollen then. You should go to a doctor and have it checked out. After I was treated for yeast and fungus, the white mouth went away, and the pain and swelling got quite a bit better. I still had EC of course.
I think the yeast infection was brought on by my constant need to smear on thick oils on my lips every hour or so. And often I would use dirty fingers when smearing on the oils. Yeast and other fungus are all over our environment, and when we put it on our lips and cover it with oils and creams, it creates the ideal environment for the fungus to grow.