The toilet was clogged and it flooded before we used the plunger, so I had to clean it up early in the morning and I’m really exhausted.
Because the hiragana ends with an う sound, you know this word is a verb. The kanji itself means exhausted and the verb version means to become exhausted, to become tired or to get tired. Don't confuse this with "to be sleepy." No, this is a different kind of tired, like a physical or mental one, like you just worked out or studied a ton.
For example, if you tried to lift two cars (つか) you'd become exhausted for sure. So, think about that as you learn this word's reading.