Somebody random got my kik?

[Help]

So I only use my kik to text my friends because I don't have a texting plan yet. I don't give out my kik or post it on Instagram or Facebook or any public profile like a lot of people do. This random girl started texting me on kik saying how she's naughty and wants me to send nudes, and she thinks I'm a guy. I've blocked her already. Only my friends and I know my username which contains a large portion of my name, so I don't know how that girl would have gotten my kik. Is there any way she could have tracked it or something of the sort, or any weird scandal that has recently happened with kik? I'm kind of worried that this may happen again. I'm a 15 year old girl. Help?