My phone has spots on the screen but not dark spots. Help?

EDIT: They seem to be fading away slowly, so hopefully they go away on their own

ORIGINAL: I woke up this morning to find I had apparently left my phone screen on while sleeping. Instagram was open all night, and now theres little squares and circles from the notifications page that show up on darker backgrounds. On white backgrounds I can’t see them, but if I open spotify or youtube they’re pretty obvious, little gray shapes. I guess that the screen being on all night the shapes kind of burned in but is there any way to fix it at home? I don’t really have the money to get my phone fixed or get a new one.