I developed a cavity in the upper left molar (third from last) two and a half years back. I consulted the dentist and he temporarily filled it, with direction to see him after one month.

Then, due to busy schedule and then due to Corona closures, I did not go to him.

However, there was no problem, no pain etc. However, I did not use the left hand side for chewing food. It remained unused for around two years. There was hole that I could feel. But there was no pain at all.

On 30-04-2021, I went to another dentist. She filled it temporarily, saying LET US CHECK IF IT REMAINS. Then for 8 full days, I used this but did not face any problem.

On 08-05-2021, I again went to her. She removed temporary fill-up and filled it permanently. But, now it is still paining. I consulted her today again, and she asked if I feel any sensitivity. I denied. Actually, I do not know whether there is sensitivity or not.

Sometimes, the pain goes, sometimes it is there. Today, after I got extra filling between teeth removed a bit, the pain is still not going.

Kindly suggest.

Note - When she filled it, even the space between the decayed tooth and next (2nd from last) was also filled. I told her to remove that filling, and she did it today. But, the pain has not gone.

I'm so glad to see you again, Story Writer!

Yes, you feel sensitivity (you had told her no). Pain is sensitivity.

You may need a root canal -- the nerve has been injured and is probably what is causing pain.

And why a series of temporary fillings? Why not a permanent one?

After temporary filling, I did not feel any pain, and even earlier for two years, I felt no pain at all. My other teeth are intact, even as there is cosmetic filling in canal teeth.

Now, I started feeling pain not after temporary filling, but after permanent one. She asked if I feel hot / cold too much on that place, and that I have not experimented yet. But, I feel pain somewhere down there, and that too, I have started feeling after permanent filling is done.

I have started feeling after permanent filling is done.
I'm still thinking the nerve has been damaged and must be removed. I'm not sure if your dentist can examine your tooth that carefully and with such detail. You may have to go to a specialist for special x-rays or scans (can't remember how they figured out that I needed a root canal) and to have the root canal (or other work) done.

Does Tylenol or ibuprofen or aspirin help the pain?

Does Tylenol or ibuprofen or aspirin help the pain?

I do not think they do. I have kept this tooth, rather the whole left hand side teeth unused and so the pain is very less and there is a sour feeling that side, and it also gives nauseatic feeling in internal left side of the mouth.

But as soon as I begin using this side even a little, the pain resumes.

I strongly suggest you contact your dentist and tell him/her all of this. You don't want worse problems and pain in the future.