Why did my friend say she was scared for me?

Okay so i was telling her how she should come with me to the gym and there was this hot guy that works at my gym and then i said "well hes like 20" and then she said she was scared for me. I did tell a couple months her how i liked my brothers friend who was 18. But its not like i would actually date them lol nor would they date me cuz im 14. Why would that make her scared for me?