Post History

Your example is first-person narration *in the past tense*.  That is, your narrator is reporting events that previously happened.

At the time of the *events*, the narrator thought the walls were moving -- no "seemed" about it.  But at the time of the *narration*, the narrator (presumably) realizes that this was an illusion, and so reports that.

Whether to used "seemed" or "felt" or any other meta-commentary depends on the proximity of the narration to the event.  For example, if your narration is presented via diary entries or letters, the perspective should be from the time those letters are written in the plot.  A narrator could be under an incorrect impression (granted, more likely about others' feelings or motives than about ambulatory walls) for an extended period of time, and you could show the narrator's changing understanding through the way those entries are written.  But that doesn't apply to a narrative structure where the narration starts after the events of the story have concluded.

It's uncommon, but I've seen present-tense narration; if you're doing that, it should reflect the character's perceptions in the moment.