Had serious anxiety for many years but haden't had a symptom for about seven years until a few months ago and it's like my brain learnt the old trick and won't relent. It basically doesn't feel like anything is real... im not real.. im not in my body. I continually feel panicked by these symptoms and i can't shake them. It's like the radio frequency we all dial into to form a reality has changed and nothing seems to match. Im in my room where i always am but it now feels all different. Could it be a brain tumour?  i keep asking myself but this seems to only feed the anxiety beast.. what the hell am I meant to do? I really don't want medication but old tricks like exercise and writing just don't work..  my brain feels captive... help...