Stuck or Dead pixel? What color is it?
I hope it’s a stuck pixel.
You can’t get it removed/fixed permanently but chances are the stuck pixel will become less nasty as the weather gets warmer. When a dead/stuck pixel happens to appear on a certain area, it means there is some kind of impurity in that area of the LCD. And since the LCDs respond to temperature and pressure changes, the stuck pixel(s) may become active when room temperature is increased or/and pressure is applied.
I, however, won’t recommend you experimenting with your mobile phone.
Good news is: my friend had the same problem with his phone and it got fixed eventually.
I don’t think claiming the warranty will work out as the LCD with up to three dead pixels is still considered "normal" according to quality standards. You can give it a try though.
Hope I helped