It's a good idea to have someone bring you a complete set of clothing. If you report the crime the police will have some very difficult questions for you. The questions may not make a lot of sense to you at the time but there is a reason behind all of them. If you feel uncomfortable answering personal questions to a man you can ask for a female officer or for a member of your local rape crisis center. Some statistics are saying that the chances of being raped are 1 in 4.
Rape is a crime.
It isn't something that you need blame yourself for. It happens because someone wanted to take advantage of someone else. It has very little to do with sex and is more a crime of power and control where sex is a weapon used against you. One thing that is nearly impossible at first is to realize that what happened to you is not something that was your fault. I don't care what you did, where you were, or what you said, being raped is not your fault.