About url capitalization

assuming I have a page, lower cases url:
example.com/cat-cat1/
while if I enter capitalized C instead of lower case, like
example.com/Cat-cat1/
it will turn to 404.

And when I site example.com/Cat-cat1/ at google, it still shows 1 result, pointing to the original url: example.com/cat-cat1/

Should this situation draw my attention? Could I avoid the 404 from entering upper case url?