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Showing physical reactions to things works for immediate reactions. But stories are not built on immediate reactions. They are built on the long term desires and goals of the characters. It is hard to show those just by moving your character around the board like a chess piece. 

And immediate reactions are conditioned not only by the immediate event, but by how the immediate event affects the long term desires and goals of the characters. In fact, immediate reactions to events are not even interesting or informative except insofar as they cast light on the long term desires and a goals of the protagonist. 

In other words, there are expected reaction and unexpected reactions. The expected reactions are those a normal person would have to an event in the absence of any reason to act otherwise. By and large, you don't need to portray these because the reader is already there. They have reacted to the event before you described the reaction, so you don't need to describe it, and your description of it is just slowing the story down. 

The unexpected reactions are where the magic is. It is the unexpected reactions that make the reader ask, what is going on here? What will happen next? So it is the unexpected reactions that you want to describe. 

But unexpected reactions have to take place in some kind of framework. An unexpected reaction with no frame at all is just random. It makes the character appear mad or the author incompetent. For the unexpected reaction to be meaningful, it has to occur in the context of a specific framework in which it raises specific questions. But establishing such a framework under the restrictions you have place on your narrative may be difficult. Not impossible, certainly. But it will be important to make sure that you are actually doing those things on which story depends, and doing them without testing the reader's very limited patience.