I'm confused about my sexuality

I've always known that I'm straight (F). I've always been attracted to men. I do admire female celebrities (I looove Zendaya) but the idea of me dating women seemed impossible. I had a looot of pretty schoolmates but I was never really excited to see them.

I have this senior in my company who's constantly on my mind. I really didn't care about her at first. But there's this one time when I went out to throw my trash and she was there outside talking to the cats. She looked at me and smiled. My heart skipped a beat. I thought she was reallyyy pretty. Her face was glowing. I didn't see her for a few days after that but her face that night keeps popping in my head. Few days later, I saw her tumbler at the table in the office, and it made me nervous. Then I saw her. My mind and stomach went crazy. I couldn't think straight whenever she tries to talk to me. I can't help but smile everytime I see her, hear her name, hear her voice. I saw her videocalling with her boyfriend and it broke my heart.

Does this mean I'm bisexual? Am I in love with her or is this just infatuation? We're not even close actually. I don't really know anything personal about her. How do I forget about her? I keep getting distracted at work because I think of her constantly.