Full coverage does not guarantee coverage for your accident. If you reside in your mother's household and are not listed on her policy as an eligible driver, her insurance company may not cover the accident. There are however many insurance companies that will cover a child with a learner's permit, even if that child is not listed on the policy as a driver.
If you were driving the vehicle without permission, you will not be covered. If you did not have the required supervising licensed driver with you at the time of the accident, there is a chance her insurance company will not cover the accident either. If you were specifically listed on your mother's policy as excluded, you will not be covered for the accident.
If your mother's insurance company was aware that you obtained your learner's permit and said they would cover you without you being listed as a driver then you should be as long as you were following the restrictions of your permit. If you did not have the supervising driver sitting with you in the front seat than you likely would be ticketed for driving without a license and thus insurance coverages may not extend to you. To find out for certain if your accident would be covered by your mother's insurance she would have to contact her agent and discuss the situation.
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