why do I have white text and a black background?

I just bought a new iphone 11pro max. upgrading from a 6s+

*my photos appear to have a strange filter when I am in Facebook

*my text is white with a black background and color links and buttons

*buttons are often unreadable because they are grey with black text

*caller ID is unreadable

I have tried everything to fix this and am baffled please help!