Like Mirko said, you’re asking the right questions and have the right attitude to the job. Only when you’re questioning your own code then you’re getting better.
People who think they actually wrote the most lit’ code ever ever... well it’s the fastest way to get outperformed by others.
Yeah, senior developers probably have more experience writing code, that's what makes them senior to you. Take this as a possibility for learning directly from somebody who is better than you, it will speak up your learning process :-)