I woke up my parents pretending someone broke in because I was bored.
Why did you do that to them
There was nothing to do at home so I decided to have some fun. My parents were so paranoid about it that it took them a while to fall back to sleep.
Lying to your parents, especially about something as serious about your house being broken into, is extremely wrong and disrespectful. They were trying to get a good night's sleep, but you woke them up and terrified them just because you were bored. They will most likely have a hard time trusting you after this.
It was just harmless fun.
I'm sure it felt like fun, but it wasn't harmless to your parents.  Even though they were relieved to learn that it was just a joke, you caused a lot of stress and lost sleep for them.  I think you should apologize, even though it was just a joke.