You say you put in an offer over 2 weeks ago, but it wasn't submitted. Wasn't submitted to the bank? Or to the owner? From your follow-up, I'm assuming it's the bank.
In that case, there's nothing wrong with your agent's loyalty. Your offer probably went to the seller. Ask your agent to be sure. Then it depends.
In some instances, banks want a single offer, so they can approve or disapprove it. In other cases, banks want to see multiple offers. (Technically, though, there can only be one ratified offer, with others as backup.)
So it's possible that your offer went from you to your agent to the listing agent to the seller. And then the seller did not accept your offer. Or, as is noted in other answers, the bank may have specific criteria regarding which offers it'll even consider.
As for your bid being $10,000 over the asking price, that really doesn't matter. Sometimes asking prices are set low to encourage multiple offers. Suppose there were 5 offers on the property, at $20,000, $16,000, $14,000, $12,000, and $10,000 above the listing price. Yours would be the lowest offer. As is noted below, price isn't the only factor, but it is one.
To return to another point in your question, yes, it's up to the seller regarding which offers to consider. Yes, that's true. It's the seller's house.
To clarify another point: It's a "short" sale, not a "quick" sale. That's not just wordplay. It's important because short sales are anything but quick. It means the lender is coming up "short" in the transaction. They often take far longer to do than a typical, traditional sale.
Talk all these issues over with your agent. While you may or may not want to continue with him/her, nothing you've presented suggests that there's anything wrong with your agent's loyalty or professionalism.
Hope that helps.