Worriedwendywoo,
It sounds like you are feeling some guilt, or responsibility for what happened to you because you had been drinking. Let me just make this clear, it is not your fault. He took advantage of the fact that you were more vulnerable having had a bit to drink. Please do not take that to mean that this wouldn't have happened if you hadn't of had that drink.
Sex and Rape are two very different things. Rape is about control, please do not allow him the control of stopping you from reporting this, through fear of him making untrue allegations.
You will be ok, it will take time for you to process this. It's not your fault, it's normal to take its time.
I believe that you may need to have an examination, they'll take swabs and take notes of injuries, which I believe are used as evidence.
They'll take your account of what happened.
They'll arrest him, interview him, and hopefully tie him up by his bollocks.
I believe that's how it all happens at least. I had gone through a similar process when I was sexually assaulted.
I'm sorry you are going through this. I hope you have some support.
Hope you are ok.