iPhone XS Max Ghost Touching

So I have had my iPhone for almost 2 years and only recently has this problem come up. I occasionally use my phone in the shower (as a lot of people do) but I mostly keep it out from being under the water. Sometimes a few drops get on it, however one time it was dropped in the bathtub. It was immediately taken out and dried off, but when I used it later the screen was sort of bugging out and ghost touching. The next day after that everything was back to normal and I wasn't worried. However, today my phone has started doing this again. It has been about 1.5 hours since it started and it's making it very hard to use. I shut it down and powered it back on but that didn't work. The phone is partly usable but sometimes it won't respond to my taps on the screen and a lot of times it will just go crazy. When I turn it off and back on again it works for about 10 seconds and then usually goes back to ghost touching. Help would be much appreciated!