Okay, I can see where your Dad is coming from...He just didn't seem to handle it in the best way. My brother is settling for the first girl he's been sexual with. As a result, he's now just dropped 8 grand on an engagement ring while she walks all over him and treats him like crap, along with treating the rest of his family the same. I think he feels like you haven't really gotten out and met a lot of people- that your explorations were limited- that one day, you will have experienced the world more to have a different view. Now, I'm not saying that he's right by any means. He could be completely wrong, and this could be the best man ever for you. However, he could be right, as well. But what I think is best is if you sit him down and have an honest heart to heart where you both talk about how you feel about this situation with the understanding that there will be no hurt feelings and that neither one of you will storm out. Don't let it become an argument. Just talk to one another...because, like it or not, he's always going to be your father. And you're always going to be his daughter. And if your boyfriend is going to stick around, this whole situation is going to have to be live-able.
Good luck.