Why is my iPhone screen black after water damage but still turns on

I was in the shower listening to music and a little bit of water got inside my phone nothing much, I didn't drop it in water. After my shower the sound sounded like it had water in it but my phone was still working so I dried it off and was still on my phone doing stuff then after maybe 10 minutes it starts to glitch and the screen turns black. After that I let my phone dry for 24 hours and when I put my phone on the charger it was working. I turned my phone and was on it for maybe 5 minutes and I put my phone down for a second because I had to do something then my phone screen turns black. I plugged it into the charger and it still makes sounds and vibrates. After maybe an hour goes by I try to force restart my phone and when I did that the screen turned on and went black again. What happened? What do I do? What does this mean?