###Human: Why is there pain in filled teeth? ###Assistant: Hi. Unfortunately, your doubt is true about it. The swollen gum and change in its color right above the tooth in question indicate that your tooth is infected and you need a root canal treatment now. Immediately, start taking the antibiotics from now, before starting take a picture of the color of gums and tooth so that you may show it to the new dentist that at this condition you started with antibiotics to avoid severity of infection and he might not give you this antibiotic coverage again and start treatment from the next step. Feel free to ask if you have any further question in mind. Stay happy and blessed. Take care.