I dropped my phone - nothing is cracked or torn from the outside, but the display slowly progressed to be blue. Touch is still working, but sort of the “blue liquid” has slowly progressed from a few drops to now a lake.

I am confused by some comments, so I hope someone can help me with my questions:

1. For this issue, do I need to change the whole display + frame?

2. Do I need to exchange the battery for this issue? I read it is easier in some cases, but not sure about this case?

The costs are a big issue for me (honestly a little shocked that only the screen is already 120€ here? I have access to all the ifixit tools and that is more than my phone had cost and my budget is 50€. Wondering if better to be without a phone for a few month and buy another second hand A3003 instead?