The statement you made will be used in Court as your recollection of what you saw/heard etc etc at the time of the incident.
It is something which would no doubt have been taken soon after the event because things would still have been fresh in your mind.
No one expects brilliant recollection months later, hence the reason why your statement is used.
I can understand that you may now have misgivings, for all number of reasons, but don't forget that there could come a time when something might happen to you and you could be relying on someone else to help you.