Do you have gum disease?  

Periodontal disease is a serious problem that is not very painful.  The sticky bacteria-filled substance known as plaque settles along the gum line and causes the gums to become red and swollen.  The gums will often bleed.   This is called gingivitis.   If the plaque remains, the bacteria will settle around the roots of the teeth and destroys the supporting bone which is called periodontal disease.  The bone loss is irreversible and the gums will begin to pull away from the teeth.  Eventually, the gums shrink away from the teeth so much, that the teeth become loose and may shift.  Bad breath often accompanies this stage of the disease.  Gum disease including periodontal disease is treatable.