Please understand that you are not alone in this and that anyone who has serious anxiety will experience many of the things that you are describing. It's not unusual for someone to be sick to their stomach, lack of appetite, have problems sleeping and headaches and I can understand that all of this is highly disturbing.
The fact that your mother isn't showing any concern may only mean that she doesn't want to upset you and is trying to put on a very calm face for you. She may, indeed, be concerned but she is keeping this to herself. I do believe that as a mother she must be thinking about what she can do to help you.
I don't know if this came on suddenly or if you been experiencing this for quite some time, but the usual first thing I recommend to anyone is that you have a medical check up. Sometimes things may be happening, physically, that can cause what you are experiencing. For example, just a change in diet or in eating some type of food may cause some of this. Even drinking too much coffee or having caffeinated drinks or anything like a sports drink can bring this on. The nervous system is very sensitive to all of these changes.
In the meantime, until you get to the doctor's, why not use two things that you'll find in our Tips column; a relaxation breathing video tutorial and another video on self-talk. The relaxation breathing can be done several times a day just to help keep you calmer and it can also be done at night to help you go to sleep.
I also have a four-minutes video on my YouTube channel which is intended to provide a relaxing scene that you can watch and help yourself by imagining that you are there walking along the beach. My YouTube channel can be found at:
https://www.youtube.com/watch?v=VPagOujjdLo. Just paste this into your browser and it will take you to the relaxing beach scene. You can even put this on your cell phone and take it with you so that you can use it to help relax you wherever you might be.
I believe that these three things can be quite helpful. You may need medication for a short period of time, but if that is suggested, I would also think that cognitive therapy with a psychologist should be considered also. Medication alone is not what we consider a complete treatment because, while it can help, it cannot teach you anything about self-help techniques. Therapy can do this.