Suggest Better Treatment For Abrasions On Lower Labia Majora

I am 31 years old, I'm 5ft tall and I weigh 107 lbs. I have some abrasions on the lower part of my labia majora and anus due to irritation from using sanitary napkin. I have been experiencing pain since last week. It's difficult to pee and wash my self because of the burning sensation. I have been taking antibiotics for 4 days but there is still no improvement. what should I do?