You come across as somewhat of a hypocondriac. Though understandable that you worry that you could lose your livelihood for a number of reasons, understand that these are so broad that they are personal to you usually, and unless you want a textbook they cannot be listed.
Relax, exercise and eat well, and you have nothing to fear. Your anxiety will otherwise become a vicious circle around doctors.
Here's a thought - when you next think of this topic, go on a run instead of reading PPRuNe.