my problem is pretty bad, and it’s on my mind/thoughts so much that it’s almost all i can think about, which only makes it worse. and just stop thinking about it is easier said than done.
It seems there would be no harm in trying Z-12 while you are waiting to see a doctor.
MAKE SURE you are not taking any stimulants whatsoever. No coffee, tea, allergy meds, HOT-ROX, Red Bull, Monster drinks, vitamin water, etc. No green tea supps, greens supps. Temporarily discontinue your multivitamin if you are taking one.
If you have been in a calorie deficit, or skipping meals, or on a low-carb diet, try increasing calories/eating more frequently/eating more carbs, respectively.
my point about the thyroid is that it could be any number of problems, so go see a doc.
Stay off the internet and self diagnosing, it will prolly make you more sick 
I agree about seeing a doctor, BUT if you are having anxiety and happen to be taking any of the above things I mentioned, and do not happen to mention them to your doctor, or say you do mention them but he doesn’t realize the significance of the ingredients, you may end up overmedicated with tranquilizers.
First things first. IF someone is experiencing anxiety triggered or made worse by stimulants, the BEST thing to do is stop the stimulants. You might not hear this advice from a doctor.
There are a lot of people on this site who use stimulants, so it is worth pointing that out.
Benzos are gods gift to earth.