Does this mean he's just attracted to me?!
Wouldn't worry about it, hon. He's just trying to tell you how you make him feel. He's definitely got a sexual attraction toward you. You were chatting on the internet, so who knows. He could have been touching himself, too.
I think it is normal for young men to masturbate. But if you haven't kissed or even hugged and he is telling you he just ejaculated while talking to you.. that comes off as little creepy to me. Sure, it could mean he's attracted to you. It's not very common for people to date people they don't find attractive. But I would think he'd wait until you two were more intimate to start discussing things like masturbation. Because, not to freak you out, but if he just told you he jizzed while you were talking to him, there's a good chance he was thinking of you while he was jacking off. I don't know, maybe that's a compliment, but I'd think it was a little creepy to admit that early on in a relationship.