Take time to rule out physical ailment. For a long time I thought job stress was getting to me - turned out to be gall bladder problems leading to pancreatic duct inflammation**. Attacks would typically hit long enough when I would try to relax. Turned out that it was a shift in the ability to digest what I had been eating without trouble for previous decades that happened to coincide with dealing with jerks.
Try not to let fear-of-fear become its own problem, particularly if it's a physical problem. I would also recommend not looking for causes on Google. There are likely to be far too many truly horrific causes with overlapping symptoms when it could be simple, like a change in the amount of coffee you are drinking.
Have you noticed any large (5 foot long) seed pods in the back yard? Do family and friends seem different with an intense interest in gardening and having you sleep just a bit longer? Has anyone wanted you to eat some mushrooms they have grown in their basement? (
https://en.wikipedia.org/wiki/Come_into_My_Cellar)
**I don't know why the pancreas and liver share a duct, but I definitely want an answer from the one responsible for that screw-up.