If you try it without preparing, yes it will. It may be too painful to get it in. Now's the time to teach yourself to open up so it won't hurt, or not as much. Douche your anus out, use good lube made for the purpose, and use a finger or very thin dildo and get yourself used to pleasuring your own anus. Bear down on your stomach rather than trying to strain to push your anus open. When you get more used to taking something a bit thicker, and it gives you pleasure, you may find a real penis very pleasurable. My gay friend from years ago, showed me how easily he can take a cock into his anus. I was quite surprised.
