Can anxiety hurt you? Also, I can feel great and then for no reason, feel really awful for no apparent reason. Why?

It sounds like you are experiencing a whole range of emotions both good and challenging. Have you noticed any patterns to the cycle?

Could it possibly be hormone related (subject to age, either PMS or menopause?).

Certain foods can create cycles of mood as well if our sugar levels drop or raise too quickly by eating/drinking sugar, caffeine, processed white foods, alcohol etc?  

Stress can also trigger different states or mind and emotions.

You also ask if anxiety can hurt you?  If you mean can it cause pain to the body, it is possible when we are stressed, and the nervous system is under pressure for a whole variety of physical symptoms to become apparent. Have you see the blog post - Baffling Bodily Behaviours - How is stress, anxiety or low mood affecting your body?

If these symptoms continue, or your have been experiencing them for sometime, with no obvious cause, I would recommend you visit your doctor or health care provider who can help with diagnosing the underlying reason. 

Once you understand the cause it is easier to decide the best course of action and if you would like further details on natural options then do get in touch again and we would be happy to point you in the right direction.