Catmusicfreak has given you excellent advise. The possibility of candida, and leaky gut syndrome, sprang immediately to my mind as well. However, I have no confidence in the "spit test". I would also strongly suggest a hair mineral analysis. Many MD's tend to check the patient for mineral and vitamin defeciencies last, if at all.
The extended treatment with Antibiotics may have killed off all the beneficial bacteria in your small intestine. As a result, a yeast named candida albicans may have taken over. It can be a very long and difficult task to rid yourself of the candida, but it can be done.
Most allopathic doctors (MDs) do not recognise candida. However, if you can find an MD who is familiar with candida that would be a very good place to start.