The song "Yesterday" by Alan Walker & Ali Gatie expresses feelings of loss, longing, and nostalgia. The lyrics depict a dream-like encounter in New York where the protagonist holds someone's hand, but never sees their face, suggesting a missed connection. The mention of being "two drunk kids on a boulevard" implies a fleeting and possibly reckless moment of happiness. However, upon waking up, the protagonist finds an empty bed, emphasizing a sense of emptiness and loneliness.

In the pre-chorus, the protagonist expresses a feeling of suffocation, suggesting the weight of their emotions and the struggle to cope with the absence of the person they long for. The line "no one knows how I feel" highlights the isolation they feel in their grief.

The chorus reflects a desire to escape the pain by turning back time. The protagonist imagines closing their eyes and making "tomorrow yesterday," wanting to hold onto the memories and emotions associated with the person they miss. The comparison of missing the person's smile to how deserts miss the rain highlights the depth of their longing. The line "ten thousand tears but you would dry them all away" suggests that the presence of this person provided comfort and solace.

In the second verse, the protagonist reminisces about a journey, possibly a road trip, with this person. The nostalgia is portrayed through watching the moonlight dance on the water and seeing their face in everything, signifying how deeply ingrained they are in the protagonist's memories and perception of the world.

The song concludes with a reiteration of the suffocating emotions and the uncertainty of what is real in the absence of the person they yearn for.

Overall, "Yesterday" explores themes of missed opportunities, longing, and the desire to turn back time to relive moments with someone who brought joy and meaning into the protagonist's life.