I have never been in so much pain than I am now.

Put an aspirin right up against it and let it dissolve. Then ice...ice will reduce the inflammation. Then...three shots of Whiskey within 90 seconds and call me in the morning.

You likely have an Abscess (Bacterial Infection) in your Gum under a 🦷 Tooth and it's affecting the Tooth's Nerves, the Root.

Call your Dentist or visit Urgent Care and get on a Strong Antibiotic (maybe Clindamycin) for a few days to stop the infection.
Then visit a Dentist, you may have a bad Cavity that only needs filing or you may need a root canal procedure.

It is likely NOT going to Get Better with Any Home Remedy or bearing with it and Hoping. It's serious.

READ: https://www.mayoclinic.org/diseases-conditions/tooth-abscess/symptoms-causes/syc-20350901

It's your gum and you need to floss the bacteria away from around the tooth. It will get bloody but you can floss the problem away.

Go to a local urgent care for temp. pain meds. until you can see a dentist.

You should be able to buy gel from a pharmacy.chemist,grocery store to relieve the pain.

Get in an abscess tooth can be excruciating

Tooth pain is tough

Gargle some salt water, mix salt with water as much as the water can disolve and gargle. It's antiseptic, antiinflammatory and might numb the pain.

Back tooth?

Tooth pain is the worst!

Poor baby

Gargle with warm salt water