Relationship Advice?Help!!?

So I met this guy at my 8th grade dance a few months ago, he was really into one of my friends, but now she likes someone and they're going out. I added him on facebook and we started talking a lot, the first day we talked he started flirting a lot, I didn't want to lead him on, but he was really nice and I didn't want to hurt his feelings either. He kept asking what I was doing on weekends and stuff, and I made up excuses, but he sent me a sad smilie and just said ';oh...okay.'; I felt really bad for him so I invited him to a beach party I'll be going to on saturday. He said yes, and acted like it was a date, and started asking me about what I liked and didn't like, then he started calling me ';boo'; I sent a question mark back because I'd just started talking to him and he just said I call everyone boo. He's been texting me all day, and he called me last night. I think we're moving too fast, and I'm only 13 (i'll be fourteen in 9 days tho) and He's 15 turning 16 soon, I'm afraid he's going to want to kiss me, and I'm not ready for that at all! He's not really my type either, but he was so nice I couldn't say no :( Now I don't know what to do, I'm nervous, but since my friends will be there I know there won't be too much pressure, I don't really want a relationship with him, because I'm starting high school, and I won't see a lot of him, we've only really known each other 2 days, and he already seems to think we're boyfriend and girlfreind! I keep making excuses so I don't have to see him without my friends there, and I'm nervous I'll run out of excuses. I don't really want to have a relationship, but he's so sweet it make me want to give him a chance, but at the same time, I don't want him to be my first kiss if I don't really really like him. Is there any way to let him down easy without making it seem like I want to go out with him? I don't think my mom or my grandparents (who live with me) would approve of him, and I really value there opinions. I would really appreciate any advice you could give me!Relationship Advice?Help!!?
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