Can symptoms tell me which type I have?

No, and this was tested rather than assumed. One study found clinical symptoms were not predictive of subtype, and the main guideline states no single symptom can be specifically attributed to overgrowth at all. Symptom-based type quizzes are answering a question the evidence says symptoms cannot answer.

Is the methane type really a different condition?

The organism is different. Methane comes from archaea rather than bacteria, which is why the newer term is intestinal methanogen overgrowth. What should follow from that clinically is much less settled than the distinction itself, and the two get blurred together constantly.

My report only listed two gases. What happened to the third?

Most tests sold measure two. Hydrogen sulfide needs different hardware, so a test without it returns nothing for it in either direction. The missing row is a fact about the test that was run, not about you.

Which type do you have?

The short answer

A positive result names a gas, and the name does more work than anything else on the report. Hydrogen and methane have published cutoffs. Hydrogen sulfide has none and is not measured by most tests sold. So these are not three equivalent boxes, and one of the three is not bacterial at all.

Start here

Which gas did your test actually find?
A positive breath test names a gas. Which gas it names changes what the result means, and one of the three is not measured by most tests sold.
Methane is not bacterial overgrowth
Methane is produced by archaea, not bacteria. That is why the methane type has its own name, and why the word bacterial in a methane diagnosis is wrong.
The hydrogen sulfide type
Hydrogen sulfide has no published cutoff and is measured by few tests. A negative on a two gas test is silence about it, not a finding.

What this stage cannot settle

How severe yours is. The published cutoffs were set to divide positive from negative and were never severity scales, so a larger number is not an established measure of a worse problem. There is also a live argument in the literature that the methane and hydrogen sulfide criteria have never been validated at all, which we cover rather than route around.

Common questions

Can symptoms tell me which type I have?: No, and this was tested rather than assumed. One study found clinical symptoms were not predictive of subtype, and the main guideline states no single symptom can be specifically attributed to overgrowth at all. Symptom-based type quizzes are answering a question the evidence says symptoms cannot answer.
Is the methane type really a different condition?: The organism is different. Methane comes from archaea rather than bacteria, which is why the newer term is intestinal methanogen overgrowth. What should follow from that clinically is much less settled than the distinction itself, and the two get blurred together constantly.
My report only listed two gases. What happened to the third?: Most tests sold measure two. Hydrogen sulfide needs different hardware, so a test without it returns nothing for it in either direction. The missing row is a fact about the test that was run, not about you.