Did my dentist do unnecessary work?

Hi - I was hoping someone could advise.

I have just started seeing a new dentist due to a move. He did x-rays and told me that I needed to re-do 2 of my fillings (I felt no pain), replace a filling that came out (I agree) and have another filling in a spot where the filling kept coming out (my old dentist told me to leave it and keep it clean).  I was not feeling any pain in any of the teeth and felt sick that I needed so much work.  I now find it odd that there were no actual cavities, just decay thathas prompted the work.  Also odd was his rush to do everything.

I went back to see him to get the the work started - I thought he'd start with the broken filling.  He replaced this with a temporary filling and said he wanted to keep an eye on the nerve to see if it would eventually need a root canal (I don't understand this).  The same appointment, he replaced the filling on my other tooth and made the new filling in the third tooth (both were deep).  I now feel extensive sensitivity and wonder if he is was just doing unnecessary work for profit? 

-Does decay need a filling? Could he have just kept an eye on this - and were there any other options?

-Do old but otherwise fine fillings need to be replaced? 

-Why do a temporary filling - doesn't it risk breaking down and prompting root canal?

I'm getting copies of my x-rays soon - there is just something in my gut telling me he doesn't have my best interests at heart.  I've had a few dentists in my life and this is the first time I have ever felt this way.

Can anyone advise?

Many thanks in advance.

 

Sorry I don't know how to edit my original post. I meant: I have just started seeing a new dentist due to a move. He did x-rays and told me that I needed to re-do 1 of my fillings (I felt no pain), have a brand new filling, replace a filling that came out (I agree) and have another filling in a spot where the filling kept coming out (my old dentist told me to leave it and keep it clean). 

decay wpould require root canal or tooth extraction i would see a different dentist and get there opinion then compair the two and decide who is better and more knowledgeable

 

Obviously it depends entirely on what this dentist has found, but I can confirm from personal experience that teeth that have lost their feelings, or even broken off, do not automatically need a root canal. They can often be re-filled or repaired. I've had this done several times.

Actual decay needs a filling, but not necessarily a root canal. However, different dentists have different ideas on what actually constitutes decay. Some prefer "watchful waiting" provided the patient has good dental hygiene and gets regular check-ups.

I'd get a second opinion if I were you.