anxiety can have a whole myriad of physical (although the feeling of anxiety itself is physical imo) symptoms and affects.
A non exhaustive list, some of which i have had
Heart palpitations - me
Chest pain - me
Indigestion - me
IBS - sometimes
Pins and needles - me
Headache - me
Vomiting - me
Nausea - me
Insomnia - me
low blood sugar (imo)
looks ive had most of the symptoms i can think of!
Shaking - me
loss of/increased appetite - both
And many others that i can't think of just now.
In an anxious state our bodies are producing lots of stress hormones - often it is an inbalance in these and the anti-stress hormones that cause anxiety in the first place (along with our thoughts and events) Again, the inbalance can then in turn lead to skewed thought patterns and it becomes a cycle. Hormones don't just work on their own, they interact together and affect different parts of the body. So an anxious person would probably be producing too much cortisol (adrenal glands). This is what is released in that fight or flight mode - often leading to that feeling in your tummy like you have gone over a humped back bridge. The trouble with anxious people - we feel like that most of the time 
then it all feeds back in a whole loop of hormones that talk to each other and get confused.
Its a crock of shit really :(
However it does help me to know that much of it is "just" down to fecking hormones.