Suggest Treatment For Canker Sores In The Mouth

Hi I have got what looks like a canker sore oh no my bottom lip but I couldn t help but notice that it has a pretty decent sized crater and is bleeding and has not gone away I use tobacco products mostly Dib smokeless tobacco and i was just wondering what it could be I seem to have receding gum lines and small intentions in my gums and I ve noticed also that I have random tiny red bumps almost look like holes in my mouth as well I m not quite sure if this could be an STD HIV or it s possible that I am getting mouth cancer or I m just being a hypochondriac either way I would really appreciate it if you could give me some kind of information to go off of