In order to do well in the final exams, John studied late into the night for the past few weeks. As a result, he started to feel sick. He had sore throat and dry cough and felt that his eyes were tired easily. Because he was very stressed, he also suffered sleepless nights.John did well in his final exams. His mother organised a BBQ party to celebrate. John ate too much that night, as a result, he had a bloated stomach and suffered from constipation.

Can I say that is the liver is causes problme?

Indigestion causes bloatedness and constipation, may be also related stomach fire or heat accumulated in large intestine.
http://www.shen-nong.com/eng/lifestyles/tcmrole_sleep_shift.html#3