Root c, extraction, dry socket?

i went to a private 3 months ago and had an examination done, i was told i needed 3 fillings. then befor i started treatment the same surgery had a new dentist about to work there and she was nhs so i put my name on her waiting list. i got an appointment about 2 months after this for an examination. this dentist told me i need 11 fillings!! i asked why the results of examinations where so different but i didnt get a straight answer. i eventually decided to go ahead and the treatment done. i dont have sensitive teeth and my gums dont bleed.when i went to my appointment i was told i was going to be having 2 fillings that day.when the dentist started drilling she said it is worse than she thought and that i would need 3 fillings this side nnot 2. a few minutes later she said my tooth was soft and had drilled my 7th molar away then gave me an option of root c or extraction. she then dressed the tooth until i decided what to do.i got no sleep all night!! the dressing was packed on a nerve i was in so much pain. i rang nhs24 and they got me an emergency app in hospital, they extracted my tooth. i went back to dentist as had bad pain again and bad taste and smell in my mouth.i had dry socket so they have packed it. pain is still there and i have antibiotics so hopefully that will clear it up, at the same time my lower wisdom tooth has flared up on the same side!! whilst packing the molar the dentist said i may need root c or extraction in 4 more teeth. im just petrified of going back for more treatment with her after all this, especially when i had no pain with any of my teeth (except wisdom teeth) befor i went to her. i brush and floss my teeth daily as meant to so how can this be right? can anyone advise me on what to do?!! i am debating on going to another private dentist for a second opinion.