I certainly don't have all of the answers.
however think about it-------------what causes us pain in our bodies? I mean what controls how we feel pain? It is our brain/nerves right? When we fall and scrape our knee, we feel pain because our nerves send signals to the brain, the brain interprets it and says, "I'm hurt". This a normal thing. Our brain interprets stuff and tells the nerves to send a pain signal back to our knee and then we feel the pain. Our brain and nerves are powerful buggers.
Let's say there is a bear approaching............. what happens---- we become hyper aware. we get the fight or flight so we can survive. We get all those lovely adrenal surges...... We have to survive. That is all well and good.
now what happens if we have our thinking go awry? What happens when we are stressed? what happens if the stress isn't relieved or realized? Our brains gets wiggy!!!! THis causes fight/flight all of the time---sometimes at a high level and sometimes at a lower level. but doesn't matter really cuz now we are "clicked" on the ON position. We never are truly relaxed. Our "fight/flight" brain is always switched on to some extent. THis leaves a body sensitized----muscles are tight, nerves are over reactive (which causes burning/tingling/buzzing) our organs aren't running optimally (ie digestions slows or speeds up).
when these goes unchecked we get in that cycle of fear-------which came first the chicken or egg?
bottom line our brains control our bodies. If our brain is scared or stressed or whatever, it doesn't send out nice calm rational signals to our bodies. Our bodies don't question the brain. the brain is THE MASTER..... Our bodies just react. That is why the answer to feeling better doesn't come from treating the physical but the mental.
some ask why do you only have symptoms that come and go? or why do some have consistent symptoms well some peeps have stuff all the time. Some have them come and go and some have a combo of the two. Guess it depends on the individual.