Hello Doctor, My Name Is Arvind 34 Yrs. My Urine

hello doctor, my name is arvind 34 yrs. My urine colour is dark yellow from 5 months. The colour changes in a day dark to light and sometimes clear. Now from 2 days my stool colour is too much dark brown rather than usual and mouth taste is bitter from 3-4 days. Please help me is there anything serious.