One would need to know the answer to a few more questions to even attempt to respond to your question. like your sex, Aproximate age, if female have you had childern, where do you hear the fluids at, have you had many bladder infections.
Hearing Liquids sloshing in your stomach, is not usually associated with your bladder. what other health conditions do you have? any Prior surgeries or tumors? are you BMs normal?