Why does my screen keep clicking in random spots without me touching t

Just yesterday, my phone started bugging out, whenever I tried to type a message to my friend, even just a simple one like 'Hi' or 'How are you?’, my phone would exit the chat. I didn't know what the flip was happening, so I played some games to take my mind off it. But then I lost control of my screen, and everything began to do confusing stuff, at some point it made a transaction on its own! At that point, I didn't know what to do, so I powered off my phone and turned it on again, hoping that everything would go back to normal. But nothing changed. Everything in the centre, top right and bottom corners of the screen were just multi-spontanuously being spammed, and it lasted for a ridiculously long time. Can someone please help explain what's happening? I really hate this thing that's happening to my phone.