in in the summer of 2013 i severely chipped two teeth, my front left tooth and the smaller one beside it. I had chipped them pretty bad and my nerves were exposed so i had to get root canals on both teeth, but at first my dentist said id only need a root canal on the front tooth which had to be redone because the first root canal was "unsuccessful" and then he decided the other tooth needed a root canal as well, even though he said there was no issue with it at the start and it would just need to be filled in. so both teeth had root canals and temporary fillings. (forgot to mention i was never once told i could get temporary filling that looked like normal teeth so i have been wallking around with two chipped teeth for around 4 years) anyways because this is a very expensive process and up until recently i've been a student and havent had proper coverage I havent been able to afford the posts and the crowns. recently my fillings have fallen out and i can smell a bad odor from the holes where the fillings use to be, my front tooth had no smell and still has half the filling in tact but recently it began to smell like the tooth beside it. in the smaller tooth there was what seemed to be gauze which smelt terrible and has since come out. I try to clean the areas as much as possible but the smell wont go away and now its very achy inbehind the teeth (it amlst feels like my left sinus has an infection- it feels like lots of pressure and gos up and kind of behind my eye) and i am concerned there might be an issue that will end up costing me more money in the long run. i currently still do not have the proper funds to finish the process as iv been told itll be around CAD$2000 and i dont know what to do because i dont want to lose the teeth. my dentist hasnt been helpful to me at all which is awful because iv been a patient for 20 years and i have had constant issues with his office.

Sorry for the long message but I wanted to give as much detail as possible before asking my questions.

first off should I get a new dentist since this one seems to be costing me a ton of money

secondly what should i do?
does this sound really bad and urgent?
are there any canadian health plans that can help me pay to get this done?
is there anything i can do immediately to save me the extra cost of getting temporary fillings done again?

any advice or different options would really help me out, its a very stressful time and i really want this process to be done and over with.