What are the requirements for Colorado Real Estate Broker to submit Sales Contract to the Seller?

I recently put in an offer on a short-sale property. After I submitted the offer, my Broker called the Listing Broker and left a message informing her of the Contract. The Listing Broker was unreachable for over 24 hours and never acknowledged acceptance of my Contract. The Listing Broker then called on the day my contract was to be accepted and informed my Broker that the Listing Broker had a client and that the Listing Broker would be submitting the other offer to the Sellers at the same time as mine, the date and time of acceptance outlined in my Contract. I am wondering if there are any consequences for the Listing Broker for not contacting the Sellers with my offer upon receipt of such. Can I file a complaint? I feel strongly that it was unethical for her to delay the acknowledgement of my Contract so that she could have her Buyers submit a Contract with knowledge of the terms of mine. Please advise.