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Eating disorders often result in tooth surface loss that will change your bite and it sounds like your new dentistry is not in harmony with the function of your jaws
This sort of work is often not addressed by many working on the NHS but a correctly made (AND ADJUSTED) occlusal splint appliance may help to ease your symptoms and protect the teeth
Long term it will be necessary to adjust or replace your new dentistry to give better harmony to your bite and jaw function

It seems it can , go back to the dentist who did it and ask to have it sorted out ,extraction should be a last resort .There are no short cuts . Your headaches due to a broken down dentition can be stopped easily . You need specialist treatment and you should travel for an assessment before you do anything you regret due to cost . Once teeth are trimmed then you cannot go back . Your kind of case can be as easily treatable as putting restorations directly on top . Try and spend your money once after having your headaches and dentition treated . Treatments on the Nhs will not allow for a comprehensive complete treatment that will stand the test of time . Consider a loan or inheritance if it is on the way .

Set yourself a budget and shop around for a specialist in occlusion after working out your priorities with regards to your teeth .

Spaces left in a dentition is long term maintenance and financial commitment . If you want to save your teeth for your life save the bone and joints first . Maintain the foundations of your teeth first , No building will stand without good foundations .