Water damage on an iPhone 6s - Sound not working (Locked into Headphone mode)

I accidentally dropped my iPhone 6s in some water for probably less than a second. I immediately dried it off with a towel, and left it off for 5 minutes, hovever I didn’t put it in rice. Luckily, my iPhone worked perfectly perfectly after I turned it on again apart from it wouldn’t play audio, because it thought it had headphones plugged in when it didn't. Can anybody tell me why this is and what to do? Also, the iPhone 6s apparently has water damage indicators, how may I find these?