Gum bleeding could be due to infection in gums as a result of deposits(plaque) .Accumulation of plaque can inflame and infect gums due to germs present in plaques hence bleeding .
Next Steps
If it is because of plaque ,visit the nearest dentist and get your teeth cleaning or scaling done .
Health Tips
Use antimicrobial mouthwash like listerine and maintain a good oral hygiene by brushing twice and using dental floss.