SUBREDDIT: r/AskReddit
TITLE: Is it normal to develop a new phobia in your 20s?
POST: For most of my life, I never had any sort of issue with water. Yet recently I've found myself feeling more and more uneasy about two things: murky water, and deep sea creatures. It's not tied to any sort of incident; I can't think of a good reason why I'd suddenly start being creeped out by it. The first instance I can think of when I felt this way was this past summer -- I was swimming in a lake, and looking around under the water when some sand got kicked up or something, because things became quite murky. Even though I was in water that was maybe 7 feet deep tops and there was no danger whatsoever, not being able to see in front of me made me feel really uncomfortable. More recently, I was in a natural history museum looking at taxidermied animals, and came across some of the deep sea fish, with their long teeth and alien-looking bodies. Shit literally gave me goosebumps and chills. And just now, I clicked [this link] on r/nosleep, and it freaked me the fuck out. They're just dolphins!
TL;DR: 
Suddenly I'm afraid of murky water and thoughts of underwater creatures, even though I was never worried about it for the first 20 or so years of my life.