What Causes Watery Stools Along With Tiredness?

Hi i was all right in morning had morning tea with one cookie no breakfast just busy with normal house work . I just start exercise chair sqout as my physio advise me for my knee .then i feel my wet trouse .i went to toilet there was watery bowl motion and some little watery vomit . After then i took the shower after than i feel sleepy and laying down on bed