Any stages that separate from my craft go on a straight downwards trajectory

[Raidriar01]

This is especially frustrating for making reusable rockets, as I cannot land them on land most of the time. Once I separate or decouple the stage just goes straight down.

[Double Timan]

I noticed my fairings leaving in odd directions as well.  There seems to be vortex whisper lines as if flying in a drastically different direction than actually moving when in the upper atmosphere so I wonder if this is related as well.