Just learned about MD

What you have right now is mostly immersive daydreaming, which is totally normal. Most MDers do start off with immersive daydreaming before progressing to maladaptive daydreaming, so I understand your worry.

However, that transition usually occurs as a result of an inability to cope with things in real life. For example, I was an immersive daydreamer as a child, but my daydreaming became maladaptive when I was 14 because of a severe anxiety disorder and the isolation that I experienced as a result.

Probably the best thing you can do to prevent it from happening is to make sure that you have other coping skills to rely on: exercise, journaling, meditation, friends you can talk to--basically anything that you can do to increase your ability to deal with stress and difficult situations. Being aware of your daydreaming and how it's impacting your life is also good. If you aren't taking the time to be aware of it, it's much easier for your daydreaming to grow out of control without you noticing it. It's much easier to prevent MD from existing in the first place than to recover from it.