Those symptoms are very normal for hyperacusis. I'm sorry you're going through this. It's a very special type of hell. During nighttime your ears are tired from the days noises, yes even if you did protect yourself. Good amount of sleep helps a lot with hyperacusis. I notice the difference in my ears immediately if I haven't slept enough.
You have to do all you can to stay all day in as quiet as you can so your ears can rest. So this means quitting working/studying asking others to help with cooking, etc. Going to doctors won't help, it will just put you in risk with more harmful noise reaching your ears.
It's very sad to give up things in your life, but you have to give yourself a proper chance to heal. Key to progress is preventing setbacks, so this means staying away from all harmful sounds. Many talk of overprotection but its a myth. Dangers of underprotecting in your situation are much much worse, so wear protection a lot.
Benzos alleviate hyperacusis pain for a short period of time, I really don't know why but many have noticed it too. I wouldn't advice you to use them daily, since benzo addiction will be gasoline to the flames. I'm not a doctor but i think you can use them sometimes, like every 15 days so you get a little break from the pain.
Don't give up yet! You're early on with hyperacusis. Things will change for the better if you manage your noise exposure well. Hyperacusis heals very slowly, usually progress is seen in months or even years. And sadly all progress can be lost in minutes, so be careful.
Your pain is terrible now, but I'm confident it can fade away. Stop going outside and fill your days with quiet hobbies. Stop talking on the phone, and IRL if that hurts you (for me internal sounds are bad too). You can improve a lot with time and quiet