Based on the context and the answer, generate a question. 

Context: This week has gone by so fast , I can not believe it is already Friday . On Tuesday I ended up sleeping for about 13 hours ... it was insane . By the time I woke up , ate breakfast / lunch , showered , and got ready it was 2 pm .

Answer:

I must have been exhausted on Monday night .



Why might I have slept for 13 hours on Tuesday ?