Yeah, I'd say it's pretty hard. Definitely do it with a guy (better yet - guys!) who's cool and knows it's your first time. And make sure he's been fucked before too, so he understands how intense it is. There are a lot of young tops out there who think they can just lube up, stick it in, and start pounding.
Start on top so you can lower yourself on his dick so you have a bit of control. Just stay focused and try to relax. Once you feel his pubes and know he's balls deep, you'll be so stoked. And once you can take a good hard fuck, you'll wish you'd started way earlier. There is absolutely nothing like having a horned up stud on top of you, thrusting away until he shows you that O-face and you feel how powerfully his dick is squirting. Life-changing!!