If a CFI was with you, he may be culpable as well. Even though you were the PIC (as sole manipulator of the controls). Technically the CFI was also the PIC, being responsible for the overall safety of the flight. Your CFI should also file a ASRS report as he probably has more experience and should have been more aware. Was there a NMAC filed also? This could be serious if loss of ATC separation occurred with an IFR aircraft.