Screen broken, logic board, or cable itself?

The other day I dropped my phone (quite hard I must admit) and later I noticed a grid of red dots on the screen. Blue dots followed, green ones were next, then they started duplicating a few mm over. This was annoying but the next day a series of red lines developed running vertically. A few days later and now the screen randomly flickers green. I would think this would be the result of a loose screen cable but on the first day, I took the screen off and replugged all the cables with no improvment.