Fluctuating Emotions

Fluctuating emotions is normal to people. We encounter different scenarios everyday that alters our mood. Though, this is different. The mere fact that I slept soundly on that Sunday night terrifies me. I woke up feeling good on a Monday morning, (which is absolutely questionable already) then doing things I usually do on a school day and yeah, that's when I knew this day is different. The moment I step foot on the area called school, saw my bestfriend in her usual cute bun, felt my heart skip a beat, I knew. I knew I fucked up. The fluctuate of emotions got into me and I found myself in a miserable situation where I'm suddenly developing feelings for my best friend. This shouldn't happen, this must not happen. Falling for your best friend isn't something normal. I should just definitely blame this to the pizza I had on that Sunday night. I shouldn't have slacked during the weekend because look at me now, I am a forever victim of the fluctuating of emotions. Now, what should I do?