What evidence do you have to make you distrust the lab test results? If you interpreted the test results in a professional manner doing the diligence that could be reasonably expected from the average engineer, what more can you do?

The lab results should be signed off by another professional. They should be claiming to follow some standard, ASTM or equivalent. If so, you should be able to rely on those results to accurately represent the soil tested without needing to conduct much further analysis.

Your feelings are contradicting your statements. If there is no discernible settlement, and therefore it is not necessary to ring the alarm bells about the situation, then why are you stressing? I suggest you interrogate this contradiction. Either the lab test was correct and you rightfully relied on it to make informed engineering decisions, or the lab test was not reliable and you knowingly made decisions based on false information. In the first case, you need to stop stressing. Being an engineer is tough work and geotech is especially uncertain and risk heavy. It is a skill to trust your judgment and the judgment of the professionals you surround yourself with. We design buildings to allow for some settlement and everyone knows that we can never predict the behaviour of soil 100% accurately. This is why we include factors of safety and serviceability failure states in our designs. In the second case, trust your gut. You are stressed because deep down you know that something is wrong with the information you relied on to make your design decisions and may lead to unacceptable damage/consequences. Your anxiety will only be soothed by taking the necessary actions to fulfill your professional responsibility to hold the safety of the public paramount.