Well, if you're under sedation then you don't have to worry about suffering the extractions, so that's something.
They'll put the immediates on as soon as they are finished. It helps protect the sockets and helps the clotting. There may be bleeding when you wake up, but in my case I was too drowsy and relieved it was over to care.
You'll probably be given some painkillers (I was given paracetamol, ibuprofen, and codeine). I actually was in very little pain. I was more tender than anything else. If I poked my face it hurt, but I wasn't in agony, just a bit swollen and uncomfortable. It's still good to take painkillers even if it doesn't hurt that much, just to help with the swelling. I imagine they'll tell you to keep the denture on for 24 hours, which also protects the sockets, then take it off to clean it and gently rinse your mouth out, before putting it back in. If you can continue to wear it, do so, because that helps the gums heal in the right "shape". You should get a follow-up appointment very soon after for them to check and adjust the denture if needed.
Immediate dentures often do not fit well at first. That's because they have to guess what shape your gums will be without teeth. If you find yours doesn't fit well, or is too bulky, or is chafing, or you just plain hate it, *please* don't lose hope. They can readjust the denture as many times as needed to make it usable while you wait for your permanent one.
I won't lie, it's a tough adjustment at first. Your mouth will feel different, your tongue will be confused, you'll be constantly aware of it, and eating and talking will be a struggle. But it passes, I promise. My immediate wasn't brilliant, but it was usable, and I could eat with it in quite easily, and looked better than what I had going on before. Since I got my permanent denture, I haven't looked back. It might take a while, but it's worth it to have a healthy mouth and a nice smile.
Some more tips: don't examine the extraction sites in the mirror! They will look quite gory no matter what, but that does not mean there's any infections. The signs to watch for infections are an increase in pain and/or a fever. And if you do happen to get an infection (rare!) just call your dentist and they'll check you out and give you antibiotics. Also don't fret over dry socket. It's a very rare complication. Be gentle with your mouth for the first 48 hours (no smoking, no straws) and you'll be fine.
Protein drinks are a good way to avoid losing weight while you're recovering and struggling with solid food. And if you're struggling to eat with your denture, you can take it out to eat. Once your gums are mostly healed, you can try soft-solids (think mashed or boiled potatoes, well cooked broccoli, mince, that sort of thing).
Rest up and take it easy while you're recovering. Try doing things that will take your mind off it, watching films or reading, whatever you like. And if you feel miserable, *hang in there*. It really does get better!
You've done very well facing your fear. Just keep the end goal in mind. No more pain! You can do this

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