Unfortunately there is a not a great answer to this other than the insurance companies have spent alot of money on computer software that determines statistically that serious injury rarely occurs in low impact cases. As a result they traditionally either deny or low ball offer on collisions that involved low impact collisions.
In California we see a lot of this also. Insurance companies here will also not offer much in settlement where there is not a lot of damage to the car the injured person is in. At the same time, we see clients that are in a lot of pain as you are. The insurance companies know they can use experts in trial that will testify as to the unlikelihood of serious injury in low impact collisions.
You should obtain needed medical care and treatment immediately and follow your doctor's advice. Do not give any statement to the adverse party or insurance company nor grant them access to your medical records. Photograph your injuries and the damage done to any property. Contact a personal injury attorney in your area as soon as possible so that you can protect your rights. You may also find it helpful to review the Legal Guides I have published on Avvo.com dealing with many of the issues you are now facing.
Do not delay in seeking counsel.
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