OP, my heart goes out to you. I had my first ever toothache while on holiday in Ireland in 2017. It.was. AGONY. The kind of pain that keeps you awake at night is pulpits, an inflammation of the blood vessels in the pulp chamber right in the middle of the tooth. It’s hell on earth.
Then what can happen is that the nerve dies due to lack of blood supply and the pain can subside fir a bit because there’s no longer a living nerve to send pain messages to the brain. But the pulp is now filled with dead tissue and bacteria feed on the dead matter and create gases which I think causes that feeling of pressure and -you guessed it - more pain.
You, poor, poor, poor thing. I would not wish it on my worst enemy! I also had antibiotics that just didn’t touch the pain.
You probably do need emergency root canal therapy. I don’t think they try to pull it until your infection has calmed down because it’s very difficult to numb you while an infection rages.
I had my offending tooth pulled in the end, after literally months of agony. Best decision I ever made, even though it’s just inside the smile zone. I swear, “Upper Left 6” will be the title of my autobiography, that wee bastard.
I hope you get the treatment you need soon. In meantime, a damp teabag surrounding the tooth for a while seemed to help me in drawing out any infection and relieving some of the pain. With a shot I would say.
Good luck!