There are all sorts of worms. Some are quite microscopic. Frankly I'm not sure myself how small they can "get". Most are yet to be classified. In other words, anything is possible.
Do you have a picture of that "fluke"?
How have you felt after using the "kit"?
I treat Asthma, and ab. 90% of the times it isn't JUST parasite related according to my notes, so don't be surprised if the Asthma doesn't go away after the cleanses.