I have accidentally fallen on my iPhone and hit on the screen with my elbow. I have noticed some grey spots on my display now.

These grey spots (5 of them) are visible on the screen even when the phone is on standby mode. These grey spots are not always in the same shape too.

The screen is intact and the touch functionalities are fine too. The touch on the grey area is also getting recognised fine.

I had thought of changing the display but when am noticing that these spots are becoming smaller, now I dont know if its a good idea to change the display.

Can someone please tell me what should I do now regarding these grey spots?