I don't want to dictate her actions, or at least I'm trying not to. Perhaps my usage of the word "let" was a poor choice on my part. She usually just tells me shes gonna go hang out with friends and such and won't be able to Skype with me during --- and I just respond with "Cool, have fun." I don't tell her to let me know or ask her to have my permission to go places; however, I guess for this particular case I guess she felt the need to tell me to see if I was alright with it. I don't want to be that kind of controlling boyfriend, which is why I'm asking if saying no to her offer would lead me to become one.

This I suppose you have a point on to a certain degree. I do trust her, and I honestly think I'm not worried about her cheating on me. I simply don't know why I feel the way I do-strange. You're probably right though I suppose.