I'm so sorry you're not feeling well. Symptoms can come and go. Usually, it doesn't go away suddenly once you have severe symptoms, but they can get better gradually. Symptoms can come on suddenly though. That's the time to examine your diet and any other behavior or things in your environment that could give clues to what caused it to flare up.
For me it took three or four months once I got on the program I have described, but for many, it takes longer. We can't even be sure we are all dealing with the same problem since many things can cause the same symptoms.