CT Scan Wait time / lump found in kidney

Hi,

Had an ultrasound for suspected kidney stones.  Turns out I don't have kidney stores but I do have a lump in my kidney and an enlarged spleen.  The consultant said the spleen is nothing to worry about for now but I need a CT Scan.  I've been given an appointment for Monday morning.  Is that soon enough?  It's a private appointment due to health cover so I've no idea if this is quick or not.  I'm concerned that the lump will get bigger whilst I'm waiting, I've got three young children.