How badly have I screwed my chances with this girl?

[rage_face]

As far as I'm aware, if a girl is truly interested in you, there's never a too early or late situation. She will chase you to get you.

I agree to some degree. But to take it to an extreme, let's say I meet a girl in a group and she likes what she sees. Then I suddenly get down on one knee and blurt out "will you be my girlfriend?"

Extreme, but illustrates my point that there are varying degrees.

In every single relationship I've been in, I've known within a month. If unsure, then err on the side of not interested.

Maybe, but see random's post where things can change for a girl.

essentially, just because a girl may have been interested in the beginning, unless you fan those flames and keep it burning, her interest will fade over time.

I agree that this may have happened in my case. However, I would like to think that if the roles were reversed, and I realised that I no longer was interested in the girl, I would cut off contact and not give her false hope. In my case the girl kept coming out with me which gave me false hope.