No, a minor cannot waive his or her claim for injuries--only a parent or legal guardian can. And the statement would not consitute a waiver, anyway, since it was not stating that you would not sue--it was simply making a factual assertion which, at most, would be held to be true as of that moment *based on what you knew them.* Since many injuries (or at least their extent) only become obvious later, saying you were not hurt at moment X does not preclude you from suing for injuries discovered later, at time Y. At most, it may be evidence that you were not injured--something the other side, if you sue, can point to to undercut the evidence of your injury, which, based on the other evidence of the existence or lack of an injury, may or not be persuasive to some degree--but it is not a dispositive legal waiver or abandonment of rights.In your state, you have four (4) years to bring a personal injury suit, so you should still be in time. It would be worth your while to consult with a personal injury attorney about the case. Good luck.