I guess it could be, if you had enough people willing to learn and speak that language, and those people live in the same area.
Is it possible for people to create their own languages?
Yeah sure. If you have a good memory and lots of patience, you can! First try making a key with all types of symbols. For example:
45=A
46=B
Except, you will make it sounds. It WILL be hard. Thee are so many sounds but it's a 1/100% chance of you finding a completely new sound.