Terrain trouble

U4 wanted to change my quality settings because my computer had been below 20 fps for more than 10 minutes, and after it changed the settings, when I went to use the sculpt tool for terrain, it started to only move the brush whenever I would scroll/change camera positions, etc. How do I fix it to how it was previously? I’m making an environment for a class that I only have about 2 weeks left in, and I can’t seem to find a solution when I search.