Since the school has a No logo policy, wearing a shirt that goes against the policy would be an act of protest or defiance. Jackie knows she's wearing a shirt with a corporate logo and she knows about the school's policy. Therefore, her intentionally going against the policy is protesting or defying the policy.
The speaker fear that no matter what happen, the tomorrow will continue as the passing of time. The future is unknow and the fruit will continue in the future.
