What does this mean? why would he say this?

So there is this guy that i like...lets call him jim. so i told my friend robbie that i liked jim. robbie went up to jim and told him that i liked him. jim just said okay. i was really freaked out at first cuz i didnt want him to know. now im kinda okay with it. but heres the thing. later on, my friends ashley and michael went up to jim and asked him if robbie said anything to him about me. jim said "umm..no?" in a confused way. why would jim say that robbie never said anything about me when he did?? i know that robbie told him cuz i hav witnesses. so what does this mean? what should i do? i dont want to ask him straight forward cuz that would be akward. and i dont want other people to bug him about it. what should i do?