Pain for 6 weeks after all teeth extracted

no stiches my gums and immediately put the dentures in my mouth.One of the "post" I had from my partials he said was hard to get out and some of the bone came with it.  I had to go back to his office a 9 pm because I filled up a grocery shopping bag full of bloody gauze. It took 6 weeks of intense pain could not function. Could not feel the top of my head for 4 weeks.  He said the pain would last 10 days.
He now wants to shave the bone in my bottom gum because it's too painful to wear the bottom dentures. I keep thinking about the pain and DO NOT EVER WANT TO EXPERIENCE THAT PAIN AGAIN. Is there an alternative?  Why was I in that much pain for so long?
Thanks in advance for your help.

[scottma]

Immediate denture always needs relining periodically. it generally takes 6 months to a year to achieve stable alveolar ridge. If your dentist can not deliver a comfortable denture, you may need to see a prosthodontist.

[StratRebel]

I would suggest a second opinion, either from an oral surgeon or a prosthodontist.

[dollydz]

Thanks for your comments, I am seeking a second opinion from a prosthodontist.