Life is too short for using a diet diary. Go ahead and get some testing! The IgG/ IgE done at a level 4 is good. I have heard people swear by their results from Alcat testing. You can review both on the web.
I cannot stress enough that you should do this now! Personal experience of waiting and getting so sick that I was almost disabled was bad! I almost be came a burden on my family instead of a provider. I am now better that before my health started to decline!