In a private residence, it's usually just called a bathroom, or a bath. If it's just meant for "convenience" (no bathtub or shower, just a toilet and sink) it's often called a guest bathroom, or a lavatory if you want to be fancy.
In a restaurant or any other public building, it's usually called a restroom. Sometimes ladies' room or men's room.
To answer your original question, yes, I have two bedrooms and each has its own bathroom as part of the suite.
I do not keep a diary. But I did when I was about 12.
You liked to chew gum when you were a kid.