I recently started having red and blue blotches appear over my photos when I try to edit them. They only show up when I am viewing and editing within Lightroom, as they go away once I export the photo.
What you are seeing are the highlight (red) and shadow (blue) clipping indicators. You can choose to show/not show those indicators by pressing the J key. Or you can turn on/off individual indicators by clicking on the little squares in the upper corners of the histogram.
Learn to use these useful tools inside LR. They can add great value to your workflow.