It sounds like a more in-depth conversation needs to be had regarding the pricing of the home between you and your agent or you and the broker. Before this conversation ask yourself why you want to adjust the price and what is it about the comparable sales data the agent showed you that you don't agree with? If you believe the agent was incorrect in his evaluation of what the market will bear, talk to his broker and ask for the price to be re-evaluated. If you want more than the market will bear, take your home off of the market.
Sounds like you have found yourself a real winner. Take out your listing agreement and there should be a section that talks about quiting the agreement. I have never been quit on in my 8 years so I'm not experienced in this. However, I believe that if you write a letter to quit and maybe even the reasons why and submit a copy to the broker of the office - who the agreement is actually with- and a copy to the agent- who was merely a representative (if you were not working with the broker). That should suffice. They may need your signature on a MLS Change of Status form if that agency uses MLS for the listing service. Otherwise start shopping around.
If you still have no resolution then take it to the local real estate board or check out your state licensee department online.
Do you want to sell your home, or would you like to sell but don't need to sell?
Selling a property is probably 80% pricing. The List price is a tool to attract buyers, so by raising the price, you just shot your Realtor in the foot (and your own foot too). Experience has shown that in order to get you the best price a couple things need to happen:
First, we need to be priced within five percent ot the selling price-that's plus or minus 2.5%.
Second, a properly priced and marketed home can expect 10-12 showings or two offers within the first two weeks of market time.
Third, we need to get your home sold in the first 30 days of market time to get you othe best price, after than the longer it sits, the less you make.
I don't know your conversation when you discussed the first price. Did you discuss what comparable homes have sold for in the last 30 days? I do not know your market, however MOST markets are buyer's markets in the US right now (but not all). We are in the middle of spring market now. Your home probably should have been listed four to six weeks ago.
Most families move in the summer, after school is out. So for that to happen, they need to close escrow in late June, so they need to open escrow in late April or early May. So you are behind the eight ball time-wise.
Before cancelling I would ask for a meeting to discuss pricing and timing. The Realtor may be right. When I meet to see if I can help a homeowner the pricing discussion is critical If we cannot agree on price, I may very well not take the listing.
Perhaps this is the opposite of what we call "buyer's remorse". I've never heard of seller's remorse, but don't be influenced by family friends or colleagues. If you were initially confident that the house was properly priced, give the market a chance to react to it. Raising the price on a property can raise a red flag with both buyers and agents.
Did you agree on the price when you signed the contract? What is the listing price? What did you want to raise the price too and why do you want to change it now? Your realtor did a market analysis, I am sure to determine what prices homes have sold for in your neighborhood. That is the probable price your home would sell for now.