Are you wondering? Because it seems like you are saying it as an absolute truth, which you do often. If you were just wondering then of course that is not a sin. But it appears that you constantly make claims without any biblical proof, and when anyone disagrees with you, you say they are going against the Holy Spirit. I would say that is a sin.
What I do often is only your opinion, and not necessarily the truth. I accept what believable people have reported regarding their experiences of heaven.
Your constant harassment and lies against a sister in Christ is duly noted.