You were wrong for obstructing the officer. You had no right to prevent entry by the police and had no authority to tell the officer she could not come in. You did, in fact, obstruct the officer. Say no more in this public forum or anywhere else online. Do not discuss this with any of your friends or family, especially those who were at the party. Hire an attorney to help you minimize the damage. Sometimes what you see on TV does not actually work that way in real life.
I feel you have a defense to this charge. I agree you should not discuss further on this site. Contact an attorney to flesh out the rest if this case. Sounds like the officer was just pissed. Would love to see the reason they try to give to justify the entry into the residence.