It's called the Baader-Meinhof phenomenon, aka frequency illusion. It occurs when the thing you've just noticed, experienced or been told about suddenly crops up constantly. It gives you the feeling that out of nowhere, pretty much everyone is talking about the subject. And you're not crazy, that's because you're noticing it more. When the Baader-Meinhof phenomenon kicks in, your brain seems to be excited by the fact that you've learned something new, and selective attention occurs. Your brain subconsciously thinks, "Hey, that's awesome! I'm going to look for that thing without actually thinking about it." So now that you're looking for it, you find it. To make it all more powerful, confirmation bias occurs after seeing it even once or twice. In other words, you start agreeing with yourself that, yup, you're definitely seeing it more.