Why am I so nervous for no reason?

This may just depend on your environment. Are you nervous around people? That may be because you have social anxiety or have a fear of fitting in and being accepted. There is a lot of pressure to fit in even if you're an adult. In addition, you may also be nervous because you are stressed out. School or work can cause that. Stress can be the main factor even if you don't think about it when you are nervous. Also, your mental health can be at a bad place to where it's making you nervous. All of these may be the cause.

It seems like he may be experiencing anxiety. Many people find themselves nervous without always being able to pinpoint exactly why. So you were not alone. it can feel like the right thing to do is ignore it and try to make it go away, but there are many resources out there to provide help with anxiety so you can better cope with it when it shows up. 7 cups website has some resources about anxiety that you can check out. It’s always better to face feelings like nervousness. Even if it’s uncomfortable. Naming your emotions can allow you to better control them. Even the unpleasant ones.