I would recommend talking to someone about it. See if there are any church-run crisis pregnancy centers around you; many of them will offer free pregnancy counseling. They can also help connect you with resources if you want to parent, and help you find an adoption agency if you decide to go that route. Some towns also have homes where pregnant women can stay until a certain amount of time after they have their baby, to make sure that you are in a safe environment and whatnot. I know there is one in my town that women who have a 'crisis pregnancy' type situation can stay at for up to 1 year after the birth of their child.
In terms of dealing with the embarrassment; that will be tough. I'm sorry that that happened to you. Personally, as much as it will suck, I would just go with being honest. Tell them you were raped, if they ask. :-/ It will be tough, but at least you don't have to feel like you are living in a lie. And remember: it's not your fault.