I like her, what shall I do next?

well, this is a sad situation. You are so utterly in love... I think that your next step should be to say hello. Walk past and say 'morning. If you don't have the courage brush her in the hallway. And i would not jump to conclutions about how she feels. if you act and asume she is acting neutral, then it won't feel akward for either of you. luck with love!