Professor being friendly or wanting more?

I can't tell if my professor is just being friendly with me or eventually wants to pursue something more. Over this semester getting to know her she has become very friendly and open with me pretty quickly. We talk a lot after class either alone or with another guy (whom she knows has a girlfriend and kid) and after a few weeks of that I went by one of her office hours just to see her. The next time we talked after class she said, specifically to me, that I should come see her every week at her office hours. I have gone to them ever since and we enjoy each other's company a lot. One of the times we talked after class with the other guy there she said that we should all go drinking and dancing together after the semester ends. Another time in conversation I mentioned that I can get people into a venue for free and she said that there was a show coming up she wants to see and I said I could get her in, so now I am going with her to a concert next month (unsure as of right now if that will just be us two or if she has other friends she will be bringing). We both smile a lot towards each other in conversation and the first class of every week after not seeing each other all weekend as she is prepping her lecture powerpoint she always takes a moment to look at me and smile. There was one week where I had to miss a class and without hesitation she said she was going to miss me. I am working hard in her class just as any other class and have straight As this semester but with all the outside social interests it doesn't seem to be just about me being a good student.

Normally I would push forward and try to find out myself if a girl is interested or not but with the certain boundaries in place until the semester is over, the suspense keeps me guessing a little. Writing it out it seems pretty clear that she probably is attracted to me but she is always pretty extroverted and social so I don't know if she is just being friendly. She is completely single and only four years older than me. I am pursuing a degree in the same field as her. I know there are a lot of intangibles that can't be described in this and I may be forgetting some details so if you have other questions that could help you guess which it is, I most likely can answer them.

So for an outgoing sociable person do these behaviors seem simply friendly or something more, or not enough information as of right now?

Personally I can't say what she is thinking/feeling, but there are good reasons for teachers to maintain professional boundaries with students, both for the sake of the students and the teacher.

So I'm curious - why the interest in her versus others in your life including other students that share the same interests as you?

Well having only four years of age in difference makes her feel more like a friend than a teacher. We listened to similar bands in high school, and are into similar things. Knowing she's already someone who has her life together helps, and it feels like she doesn't judge me at all. She is good looking and is just generally fun and comforting to be around. The stories she has had of her personal life make her sound really spontaneous/adventurous at times which I tend to like, because I get bored easily with a repetitive life, but because I am introvert yet spontaneous leaning, having someone extrovert and spontaneous would bring the spontaneous side out of me more I think. The immediate feelings of acceptance between each other have brought out that "clicking" feeling in me. There is a girl in her class that seems into me too but I don't know what it is. When I compare the two my intuition immediately has more trust for my professor as a person.

The boundaries definitely make it hard to tell too so I'm just waiting it out. It will at least keep things interesting for now I suppose haha. She's only my professor for a little under two months. After that she won't personally offer any classes I haven't taken elsewhere and I'll be done at that school after spring anyway.