What should be done during the time a person is seeking medical treatment and speaking with a claims adjuster?

It would be advisable to get a second opinion from another doctor, preferably an orthopedist regarding your neck injury.  Physical therapy may improve your condition.

When you complete your medical treatment and are released by the doctor or are declared to be permanent and stationary which means you have reached a point where no further improvement is anticipated, obtain your medical bills, medical reports and documentation of any wage loss.  Your personal injury claim will consist of these items and should be filed with the claims adjuster of the at-fault driver's insurance company.  Compensation for the medical bills is straight reimbursement.  Compensation for wage loss is straight reimbursement.  The medical reports will document the nature and extent of your injury and will be used to determine compensation for pain and suffering.  Compensation for pain and suffering is an amount in addition to the medical bills.  If you are dissatisfied with settlement offers from the insurance company, reject the settlement offers and file your lawsuit for negligence against the at-fault driver.  If the case is settled with the insurance company, NO lawsuit is filed.  If the case is NOT settled with the insurance company, you will need to file your lawsuit for negligence against the at-fault driver prior to the expiration of the applicable statute of limitations or you will lose your rights forever in the matter.

Until you complete your medical treatment and are released by the doctor or are declared to be permanent and stationary, it would be premature to try to settle the case because you wouldn't have your total medical bills, final medical report and total wage loss.  You need to file your personal injury claim with the at-fault driver's insurance company in order to receive a settlement offer.  Again, don't try to settle the case until you complete your medical treatment.  Once you accept a settlement offer, you can't go back to the insurance company in the future and ask for more money.  You will be signing a release of your claim (giving up your claim) to receive your settlement check.