Lets see, you hired an agent to assist you in the purchase of a home. I think you found a home you want to purchase...so yes, the agreement is binding.
It would be my recommendation to use a realtor, even with ..perhaps ESPECIALLy with a FSBO. Your realtor is not just a tour guide, but trained and experienced in the executiion of legal and binding contracts. As Your realtor, he/she will be looking out for YOUR best interests, security, and avoid any of the pitfalls of fraud, negligence, that DO occur. and run a comparitive analysis for you, work thru the inspection negotiations and more. let alone the handling of earnest money, escrow, lending, etc.
Now then, secondarily this agent can write the offer, with the commission to be paid BY THE SELLER!!, if the seller gets the idea you will not proceed without representation, paid by the seller,...they often will pay for an agent to represent you and assist in getting the sale closed properly.
Many many fsbo sellers offer agent compensation. I certainly do not recommend doing it without one.