Wtf is wrong with my clothes iron?

Today I woke up and decided to iron some things. It turns on just fine but while I was ironing, little tiny rocks or pebbles almost like dust in size appeared whenever I used the mist/spray option. There was water in my iron from over a month ago hahaha....and it was pretty dusty before I cleaned it. The debris/whatever it is is white. Does anyone know what this is? I'm scared and think its bug eggs or something...