How do I cope with how I m feeling? Advice, tips, anything?

There is this really cute girl who works at the library on my college campus. I can t really explain how I m feeling but it s kind of like a mix of anxiety and happiness with some other emotions. Normally I see a cute girl and I would I would think about her for a couple hours and just move on. However, one day I saw this girl who I don t know (nor does she know me) and she works at the college library. I ve seen her everytime I ve been to the library. But my God she is beautiful and I can t like forget about her. Like I said my mind just goes crazy when I see her like at one point I panic for some reason, then I m happy, then I m depressed, etc. Idk I don t even know her and she s all I ve been thinking about and I can t stop. I feel like I want to rip my heart out of my chest and throw it out the window or sonething. Is this behavior normal for me or what? How do I deal with it?