What Causes Red Spots Under The Teeth And Swollen Glands In Neck?

Good afternoon, I have a couple of small red spots under some of my teeth on one side only which are really painful. Also a bit of earache. gland swollen under the neck only on one side and face is sore to touch on one side. Is this a sinus infection? I went to the doctors and he did not really tell me what it was, just to take paracetamol.