A notable swollen gum is a indication of infection of your gingiva ( gingivitis). various factors are responsible for this. We can only treat if we know the cause of it and eliminate it.
Immediately see a dentist. That will help in knowing the root cause of this problem.
Next Steps
visit a dentist. Get a through scaling done.
if it still doesn't subside in a week or two we can opt for taking a complete x-ray and consulting a periodontist.
Health Tips
change your brush ( use a soft bristled brush and change it every three months)
brush gently twice daily...
rinse your mouth after every meal
avoid snacking in between meals