Foul smelling secretion from the gums can definitely be a sign of him problem. In case if him disease there will be pockets where there is chance of food logement and is not self cleansable. This food get putrified and can give rise to foul smell.
Next Steps
Though meeting your nearby dentist is mandatory to come to final conclusion, Doing forceful warm saline rinsing, massaging the gums after brushing, and a good mouthwash will help u as home measures.
Health Tips
Get a Dental check up done