Please help. Feeling deep despair over dark spot on dental x-ray (photo attached).

Any opinions on this would mean a lot to me. Almost two years ago, a dark spot was spotted above one of my top front teeth.  I waited to get a second opinion.  I was told it was either a large abcess or a cyst.  I finally had a root canal done late last year and was told that would clear it up.  Well today I had my first x-ray since the procedure and the dark spot is still there and has grown a little (see attached photo).  What is going on?  

I already have very high anxiety since loosing both my parents in the last 11 months.  Now I am convinced this is cancer and heading into the weekend I'm at a low point.  Reaching out to you guys for any thoughts.  Thank you.