So this girl and I have been friends for about a year now and the relationship has been escalating a bit with a lot more flirting than usual. The thing is, I don't know if she's intentionally flirting or just doing so for no reason at all.

Just a few parts of some IM conversations we had:

: I want to give you a bear hug
: *bear hug*

: Hey formal is coming up!
: End of this month!

Later when we were hanging out, she mentioned the formal again, but never really talked about it after she mentioned it. There wasn't a lull in the conversation or anything, she just kind of brought it up. Later that day we came up with a nickname for each other when we heard some guy pass by us say this randomly to someone else.

: "Little red"

: You're my "little red" :)

Besides IM conversations, there was some other things she did like twirl her hair around her finger while talking to me, lean towards me often, and she's grabbed onto my arm and held her head there for a few seconds.

Anyway, my main question is, what are your thoughts on all this? I was planning to ask her to go with me to the formal since she's mentioned it twice already. Should I make her a cute card while inviting her to go with me?

Yes!

Go for it!

She definitely wants you to ask her to the formal. That's why she has brought it up twice. Do it now before someone else beats you to it!

Go git-er boy!