Writer is defining some very difficult times of various people of different situations and comparing that to hangovers.
Like an ageing school teacher who is divorced and her life is felt like same every day. She is always tired and smoking mostly.
Like a student who have an abusing mother and going school is very painful and unhealthy.
Like travelling with a bus filling throat with unbearable smoke and writer is also comparing himself with a dog which is no longer active and afraid of going out because of the heavy thunder and lightning.
Like an employee who always feel under the weather and does not perform well.