What to do if water is underneath your screen

I was taking a shower with my phone on the sink listening to music and when I got out I saw small droplets of water on my screen so I wiped them off and turned on my iPhone SE when I noticed that the screen was brighter on the lower right corner and it proceeded to expand until almost my entire screen was brighter I do not know what it was. I admittedly used my phone to search for what to do. I then powered off my phone and covered it in rice. I do not know how to remove the battery or SIM card so I did not attempt to remove it for fear of damaging my phone even more. I was wondering if the rice would help and if so how long should I keep it there? I have heard different people saying to not soak it in rice or to soak it in rice for 24 or 48 hours. I would like to know if I am causing damage to my phone and what to do?