Using Realtor on Zillow? (What are expectations)

Hi all! First time home buyers, and just getting started. We don't have a realtor yet but wanted to go ahead and start looking at houses. I set up our first house visit through Zillow, and assumed that the realtor we met with was the seller's realtor. When I went to set up a second visit it asked if I wanted to use the same realtor, and I realized my mistake...

We liked the realtor, but definitely want to ask around and get recs before choosing an official realtor.

Questions: Would it be rude/breaking unspoken expectations if we use the same realtor to visit houses until we find a realtor? Would it be better to ask Zillow to find us a different realtor every time? Is there a way to visit a house without a buyer's realtor? Do Zillow Realtors expect to just be a stand-in for people who haven't found a realtor yet?