Sensitivity after filling

So I went and got a filling a week after my little brother unexpectedly passed away..which I shouldn't have done. This was early February.

During the filling, I heard something like there was an "imperfection" and the dentist made the filling bigger.  I was so out of it that I didn't ask what happened.  He told me there would be sensitivity, and there was and it never went away.  Then a month or so later, I couldn't eat on that side anymore b/c it hurt.  

I couldn't get an appointment with the same dentist, and I wasn't sure I wanted to see him again if he screwed up my tooth.  I saw another dentist and she said that she couldn't see anything wrong, and put a new filling in.  I will eventually have to get it crowned b/c the filling is so large...she said not close to the room though.  And she's not certain the new filling will fix the sensitivity.  

I'm just upset that I went in there with a normal sized cavity and now I have a giant filling that I will have to get crowned!  Any ideas what is going on?