I felt those sensations in my Bell 47 days. That aircraft has nothing to use as visual reference cues with relation to a horizon, so anything much over, say, 50 ft. wasn't fun.
One day I got pissed off at myself and I forced myself to "learn" to be comfortable at altitude. (Being of weak mind it didn't take all that long).
As I said it was easier in aircraft with centerposts such as 206s and/ or sectioned bubbles such as Lamas or Allouetes.
Still, maybe I'm just gettin' old - if I don't have anything hanging from the hook, I still like being able to drag my foot if I want to.
C Ya