Is it wrong that I pretend I'm ticklish so people won't touch me?
Why don't you like to be touched?
I don't know. I guess it's normal to not want people touch you.
Yea, its fine to not want people to be touching you. There is no need to lie about it though, no need to be ashamed!
Well, I've started to like it when people touch my back and arms.
That's good that you are becoming more comfortable with people touching you! However, it's still best to just be up front with people about how you are feeling. I'm sure people will be understanding if you simply tell them you don't want to be touched instead of lying about being ticklish.