Samia's poem uses a flood as a picture of being overwhelmed by your own disappointment. The water isn't a few puddles but torrents, and the speaker says what is breaking through the dams is "defeated self expectations": the pressure of not living up to what you hoped to be. The dams stand for the ways we try to hold ourselves together, and they give way almost at once.
The poem keeps raising the stakes. Concrete fails, so the speaker imagines diamond, the hardest thing possible, and says even that would eventually crack. The buildings swept away are "meticulously constructed," yet they fall like houses of cards, which suggests a carefully built life or sense of self that can collapse in a moment.
The mood is bleak and powerless. There's no rescue and no hopeful turn at the end, only the sense that some feelings are simply too large to contain, however strong you try to be.