Girl Advise Please!!!?

I'm a junior in high school. I have a crush on a girl. It started last year when she sat next to me in my English cl. She seemed interested in me too, but, unfortunately, the school year ended and i never saw her until school was back in. Now she's only in 2 of my cles and she sits in the opposite end of both cles. I have recently been trying to talk to her, but every time, she sounds extremely sad or flustered and barely talks. That leads to me feeling uncomfortable and i just say bye and walk away. What should I do? Should I abandon my dreams to be with her, or should I do something else? Please help!!!! By the way, I just want to say that we were both matched for each other in a matchmaker test that our school's ASB provides.