What should I do if I do not like research in a particular field?
There're a few ways to interpret why you don't like research in this field:
First way: you don't like the particular field because the papers are confusing and technical. In this case I want to point out that from your description, you've done spectacularly well. I was barely able to understand one single paper when I was an undergraduate, and you understand seven! You have nothing to fear about graduate school in this field, in that case.
Second way: you don't like the particular field because the topic is boring. This is a more serious objection. If you genuinely find the topic boring (that is, you find the end goal boring, even if it is achieved; or if you find the problems that you'd solve daily uninteresting) you might want to work on another topic.
Third way: you don't like the particular field because the topic is complicated and difficult. Unfortunately enough, graduate study in virtually every field is complicated and difficult. That's a big part of the reason why many people never attempt it. If you genuinely do not like complicated and difficult things, you might want to avoid graduate school entirely.

If I go to another field in physics, what should I do to see if I like researching in that field?

Ask someone who's researching in that field. If you don't know anyone to ask, try asking the graduate students and/or professors in your department, even if they don't work in that field. It's possible your department will have a graduate advisor of some kind. Here's an example from Stanford. Even if you are not a graduate student, you could still ask the graduate advisor.