i have had things happen like that and then my sight gets nocked out of place from i guess getting nocked around then i fix it and the arrows is fine. i dont know even though it was like that try it tommorow and see if you get the same results it could be you because you know it is a bad arrow and you are expecting a bad shot and then there is a bad shot, atleast that is what i thought i went out to shoot and it is fine.
hope this helps