Gum disease is often silent, meaning symptoms may not appear until an advanced stage of the disease.
However, warning signs of gum disease include the following:
Red, swollen or tender gums or other pain in your mouth
Bleeding while brushing, flossing, or eating hard food
Gums that are receding or pulling away from the teeth, causing the teeth to look longer than before
Loose or separating teeth
Pus between your gums and teeth
Sores in your mouth
Persistent bad breath
A change in the way your teeth fit together when you bite
A change in the fit of partial dentures
Millions of people don't know they have this serious infection that can lead to tooth loss if not treated.
Information as per AAP https://www.perio.org/consumer/gum-disease-symptoms.htm