I told the girl I like I liked her but pretended it was someone else telling her
Why did you want to deceive her like that?
I was not sure if she would like me back.
That's nice you found someone to love, but you need to just be upfront with her and not beat around the bush. It is annoying to not be straightforward and cause a lot of problems like this.
I am nervous about being up front with her.
Misleading her is not the way of dealing with this. You need to be honest with her, lest you lose your chance with her at all.