I am sorry to hear this; you need to do stool and antibody testing for not only protozoa but also helminths and nemotodes. Most tool tests are completely unreliable and done by lab technitians who have not clue how to find parastites. Also, even 3 stool tests in a row are not sufficient.
Herbal and things will help but will not cure it. And you need to list your exact symptoms?
Go and have your doctor check for Esinophilia, toata IgGs. And then approach a doctor who checks for infectious disease.