Yes, playing against someone who allows you to develop no rhythm, can throw off your game.
However, having said that, let's complicate things a bit.
If someone gives you inconsistant pace/speed/depth/placement and so forth-- and it throws you off (as it would do to many people) then it means you need to work on your basics.
If your basic mechanics/strole production/movement/anticipation.positioning are solid, then you would easily adapt to the situation/provide your own pace/get into position/stroke through the ball/and hit the ball cleanly.
It is always easier to play against someone who hits the ball consistantly/at a good height/constant speed and so forth, but in a match an opponent will want to do the opposite and throw you off your game.
Practice for this by having someone toss you bloopy balls, just out of reach, in awkward positions. Practice hitting them (at a medium pace) solidly back with a specific placement in mind. As you find your "rhythm" begin to hit a bit more forcefully/deep/solidly until you feel comfortable creating your own pace.
I suspect that your whole game was thrown off slightly, not just your grip. You just focus on the grip because that is where you normally feel the good contact with the ball-- and you lost that feel because your whole game was off sightly.
Good luck,
B
