Slow down and take a deep breath. Although I can understand why you may not want to have your parents present when the police talk to you about the circumstances and what went on, it may be a good idea to face the music now and make sure that your rights are protected.  Parents do that best.  They will find out eventually, believe me.  The police will come to your home or school or where ever to speak with you.  They have an obligation to investigate and great power in tracking you down.  Avoiding talking to them is not a good idea.  It will only make things worse for you in the long run.  You have to tell the truth and what you remember. Good luck.