Unless you are absolutely bowled over by the first property, then wait and view the second. You can make offers and pull out, but as it's the same agent, you don't want to appear flaky.
I wouldn't be concerned about liking one of the first places you view. One thing you do gain from viewing many properties is that you get a lot better at doing it; spotting damp, subsidence, leaks, etc.
Unless you are absolutely bowled over by the first property, then wait and view the second. You can make offers and pull out, but as it's the same agent, you don't want to appear flaky.
I wouldn't be concerned about liking one of the first places you view. One thing you do gain from viewing many properties is that you get a lot better at doing it; spotting damp, subsidence, leaks, etc.