I have a larger implant in my right and i had weird feelings in mine not quite like what you’ve described but with mine it was more when i lifted my arm it feel like my boob was pulling, which didn’t happen with the boob with the smaller implant.
I don’t think it will be moving but you might feel a little more in that one as there is less breast tissue in it. If you get really concerned about it then ring the nurse and just have a quick chat about it to her 😀
x