Gap in gums, and a lump

I have a strange lump on my gums, on the top, between two teeth.  Long ago I had a tooth that refused to fall out.  It was completely loose, but the nerve was still intact, so it hurt too much to pull out the rest of the way.  The gum healed there when it finally fell out a few years later.  But now the gum is receding in that spot, and there's a hard lump above it.  It's been slowly getting worse for months now.  It doesn't hurt at all.  I can't afford any dental care though so I'm kind of scared :(

BTW I know my teeth on that side of my mouth are in horrible shape... When I had a ****** life when I was younger and didn't take care of myself at all.  I regret it now and brush and floss every day, but the damage is done.

(this is a picture, you can't really see the lump in it though.  It's not very large, but it takes up the area above the gap, and the tooth beside it. http://i536.photobucket.com/albums/ff322/KionaDark/tooth.jpg)