Everything makes someone with anxiety nervous; whether it is letting someone down, or messing something up. They are always nervous about something, even if it is not obvious that something should be making them nervous.
When someone has an Anxiety Disorder, they are innately always searching for something stress about, even when a specific stressor is gone. Someone could be stressing an insane amount over a test coming up, but instead of being relieved that it is over, someone with anxiety will continue to worry themselves sick about how the result of the test will turn out.
People with anxiety are always concerned with the worst-case-scenario. The thought of something going horribly wrong does not leave the mind of an anxiety-ridden person. 'What if this happens?' or 'what if it doesn't work out this way?' is always on that person's mind.
The amount of stress on someone with anxiety causes mental breakdowns in multiple forms. A person with anxiety will often break down in tears, have an Anxiety attack, etc. because the body cannot handle the level of stress placed on this person.
It is extremely overwhelming having so much on your mind all the time, so people with anxiety sometimes are so wrapped up in their thoughts that they do not speak. There are so many questions and concerns in their own mind that they do not even have to speak out loud.
This one is pretty self-explanatory... being up all night stressing out is something almost everyone with anxiety can relate to. Anxiety does not rest.
Anxiety is scary. It causes other people to seem scary, it causes daily activities to be scary, and it can even make you scare yourself.
Anxiety makes it feel like everything is closing in on someone with Anxiety. It is like walking into a tiny room, and all of the walls are getting closer and closer.
People with anxiety (especially Social Anxiety) are immensely nervous of what other people think of them. It can feel like every single person is staring at you and pointing out your flaws. The feeling can be compared to being on a stage in front of hundreds of people naked, when in reality, you are just walking down the street, minding your own business.
It is a struggle to get through a normal day with anxiety. Anxiety can physically make someone feel like they are drowning in their own life.