The paperwork at a first showing moves fast: a sign-in sheet, a disclosure about agency, sometimes a one-page "touring agreement", sometimes the full representation agreement. Two of those are contracts, and they do not announce themselves. A meaningful share of buyers who answer "not sure" when asked whether they signed anything turn out to have signed something binding.
The distinction that matters is scope. A touring or showing agreement typically covers specific properties on specific days, often states that no compensation is owed, and expires on its own. A representation agreement covers a market for a term, states a fee, and usually carries the exclusivity and protection-period language that outlives it. The titles are not standardized, so the words inside decide which one you are holding.
How to find out
Ask for a copy — you are entitled to one of anything you signed, and a photo of it from the agent's file is fine. Then read for four things: a fee, a term with dates, the word "exclusive", and anything about what happens after it ends. A document with none of those is very likely a tour-scope form. A document with any of them is a contract with a clock running, and knowing which clock changes what your options are.
None of this needs to be adversarial. "Can you send me a copy of what I signed on Saturday?" is a normal sentence, and an agent's reaction to it is itself information.