“Ok.” has no attitude until your insecurity reads it out loud.

Short text carries no tone, so the reader supplies it, and what gets supplied comes from whatever you were already feeling. The message is genuinely neutral, and the voice you heard it in was yours. That is why the same two letters can land as fine on a good day and as cold on a bad one.

When a message stings, try reading it again in a flat voice, then in a warm one, and notice that both fit. If it still matters, ask rather than interpret. A one-line question resolves in ten seconds what an evening of rereading will not.