My first exposure to quicksand giving me the heebie-jeebies was that Steven Spielberg's Amazing Stories episode wherein their kid died and got reunited with his now dead wife. I guess it's intended to be touching/bittersweet, pero it really made me fear quicksands.
I wasn't afraid of the dark, nor was I afraid of aswangs, manananggal, etc.
No, my young dumbass was afraid of this (first 5 seconds pa lang tangina I was scared shitless (literally would cry sa first 5 seconds pa lang ng music). Never stayed to finish the intro, never even waited to find out what the hell this game was... until like I was 16 (ish).
I was really furious to find out SEVERAL YEARS LATER that this was not even remotely close to a horror game, but a fucking Mahjong game (Dragon's Eye Plus Shanghai 3). Really glad that no one really remembered from my circle of friends, or else they would have NEVER, ever let me live this shit down LMAO.
Camera flash. You can take photos of me just fine without flash (or if we're outside and the flash isn't as noticeable), but as soon as it's indoors and you need flash, I'll be out.
Evening local TV used to scare me. Unsettling commercials (Karne Ka Lang sa Hazing, Pray the Rosary bumper), gory news reports/true crime shows (Calvento Files), and horror anthologies (Tales from the Darkside, Regal Shocker).