It stings in the shower” refers to mental health and thoughts that you may have pushed away become more vivid in the shower, and clearer to remember. It also referrers to the fact that depression can be stronger in the shower, and that self-harm provoking words will “sting”.

Another interpretation is that if you have recently self-harmed (cut yourself) the shower water may sting it. That is also what it could mean.
Teacher: “Lola, are you alright.. You seem down lately

Lola: “It stings in the shower
by urbanexamples October 22, 2020
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