D.,
You are not losing your mind. Two main categories of fear with anxiety are losing one's health, and losing one's mind.
For those with health anxiety, real symptoms are felt, but they are not indicative of disease, but rather a manifestation of the anxiety.
For those who worry about
schizophrenia, the symptoms are going to feel indicative of 'going crazy'...but just like the physical symptoms...they are simply brought on by the anxiety.
Anxiety can't develop into a more serious mental condition...it can just become worsening anxiety.
You had some really good days previous to this happening, so get back to working your coping skills...stay away from Google searches...and get back to that place of feeling well again.
You can do it...and we are here to cheer you on!
S.C.