No. If a real estate broker wants an exclusive listing agreement with a client (and they always do), they need a written contract, and they'll have a very difficult time claiming the right to a commission without one.
Avvo doesn't pay us for these responses, and I'm not your lawyer just because I answer this question or respond to any follow-up comments. If you want to hire me, please contact me. Otherwise, please don't expect a further response. We need an actual written agreement to form an attorney-client relationship. I'm only licensed in CA and you shouldn't rely on this answer, since each state has different laws, each situation is fact specific, and it's impossible to evaluate a legal problem without a comprehensive consultation and review of all the facts and documents at issue.
Do you mean that you clicked on the MLS listings by invitation from the Realtor? Was there some kind of contract that stated that you were bound if you clicked? Based upon what you have written, it sounds like someone is trying to manipulate you, but there is a possibility of a contractual relationship under the right circumstances. The realtor, however, would have to have done a lot more than click on listings.