Help Power button stuck

[Dream_Catcher]

I accidentally dropped my phone in the bath. I instantly put it in rice and left it overnight. In the morning it seemed absolutely fine but now the power/screen lock button keeps getting stuck down. It locks my phone then will bring up the unlock screen but if I pull the ring up it'll lock my phone again also if I take the battery out then put it back in again starts up automatically like I have pressed the button.
Any help would be much appreciated.