A lot of lower back pain ultrasound showed free fluid and enlarge kidney blood tests were normal i'm always exhausted does this explain the tiredness ?

Need work up: Need additional testing as to why have ascites (free fluid). Liver, kidney and heart disease are the usual culprits. Enlarged kidney is a relative term. Would purse testing. Treatment would depend on cause of the fluid gain. A blood work, urine test and physical exam should offer insight. Often patients need diuretics (water pills) to get rid of fluid gain. Establishing cause is KEY.