I Get BCG Treatment For Bladder Cancer. Sometimes I Wait

I get BCG treatment for bladder cancer. Sometimes I wait for two hours and have my bladder emptied using a catheter at the doctor's office. Sometimes I go home and wait until the two hours are up and then start to void the BCG as directed. I find it takes me longer to feel normal by going home instead of having it removed by catheter at the doctor's office. Is this the normal result?