It’s ok to have an opinion on something even if you’re not an expert in that field. But to keep that opinion (whether it be informed or uninformed) may not be logical once new information comes to light.
You should focus on having the right answer, even if that means you were wrong before. Strive to be right as often as possible, but don’t stick with your original opinion that you know is wrong just so you don’t have to say you were wrong before. Everyone is wrong about many things over the course of their lifetimes. But the ones who are generally viewed as the smartest and most successful are the ones who are able to admit when they’re wrong and to move forward when they are presented with more recent information.