Hi i have a dental question and I am very worried,?

Hi i never had insurance to go to dentists on a regular basis and one day i got a cavity on my bottom tooth. I let this problem go as i did not have insurance or the money to see a dentist and i thought it would be ok as long as i brushed my teeth daily. The cavity ended up getting worse and got so bad that half of my tooth ended up breaking in half an the inside of the tooth where the cavity was also fell out. I know i am stupid for what i am about to type but even after this happened i still did not see a dentist i just kept brushing my teeth daily as usual. One day i started getting a severe throbbing pain almost an unbearable sharp shooting pain in the root of the tooth and i could not even chew on the right side of my mouth and still to this day i can't or else it hurts severely when i bite down on that side. The sharp throbbing pain finally went away after about 3 straight days of agonizing pain but the problem now is all of my lymph nodes are swollen (the node on left side of my face on jaw line and the node under my jaw right above adams apple) both of these have been swollen without going away for at least almost a year and i recently went to the doctors thinking this was cancer related because i also lost some weight but i got a CT/PET scan and everything came back normal. Until recently as in this past week i had no idea about how a dental issue can lead to swollen lymph nodes and also read that if left untreated it can lead to bacterial infection of different parts of the body such as the brain and that is when this really started to scare me. I read that when lymph nodes show up and it's dental related to something such as a tooth decay then it means it is in a very serious stage. Please any information or advice on this problem will really be appreciated such as what do you think this issue is and if it is very serious or not. I just recently got on MassHealth and as soon as my car gets fixed in 3 days i am scheduling a dentist appointment as i am very scared and freaked out with what i was reading.
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Well, whatever you do, try not to freak out so much because you're only suppressing your immune system. I think I had similar case just without the swollen lymph. I actually had to get a root canal since cavity went in deep.. but in your case, it does sound like an infection and yes they can end up in your brain if left untreated. Once you go to dentist, I'm sure doctor will give you antibiotics and that should probably do the trick. Also, try to go to dentist often. Our mouth is the most filthiest place on our body where it attracts lots of bacteria. And didn't the regular doctor take a sample of the lymph area to get it tested to see for type of infection?
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