Samsung Galaxy S5 SM-G900V weak display with spilled colors

I got the phone in full functionality, in fact the best from three I bought second hand although cost me just about 11 dollars. Only problem was with broken glass in upper side around camera and speaker I know it is needed to change the glass, but I thought all the time I will do it later. After many months in normal use, once I had to take him on the lighter rain, then suddenly display begin to flash white strongly. Immediately I turned him off, pull out the battery and tried to wipe all from water. From that time display lost brightness greatly, and colors are spilled especially when scroll over touch. It is possible to repair the display, or I need to replace it? Thanks