The groinal response: why a physical sensation proves nothing
The single most common reason people with POCD conclude the worst is a flicker of sensation when they checked. Anxious attention aimed at the body produces sensation there, in anyone, about anything.
You had the thought, and then you did the thing that has become automatic: you checked. Turned your attention downwards to see whether your body was responding. And there was something. A flicker, a warmth, a sensation you could not confidently say was nothing. And that was the moment the fear became a verdict. Thoughts you could argue with; this felt like evidence.
That moment is the single most common reason people with POCD conclude the worst about themselves, and it rests on a misunderstanding of how bodies work.
Attention produces sensation
Try this, right now. Turn your full attention to your left hand. Notice what is there. Within a few seconds you will find sensations: warmth, tingling, an awareness of the pulse, a slight heaviness. They were not there a moment ago, or rather they were, but you were not attending to them, and attention is what brings them into awareness and, often, what generates them.
Now consider what happens when anxious attention is aimed at the groin. Frightened, urgent monitoring rather than calm curiosity, with the whole of your fear riding on the result. Blood flow changes with anxiety. Muscles tense. Attention amplifies whatever is there and produces more. The result is sensation, reliably, in anybody, about anything. It has a name, the groinal response, and it is a product of the checking rather than evidence of anything about you.
Why it feels like proof
The checking is set up to find something. You are asking "is there a sensation that proves I am what I fear?" with terror, rather than "is there any sensation here?" with an open mind, and any sensation at all gets read as the answer. A neutral flicker becomes a response. Tension becomes arousal. The ambiguity of ordinary bodily noise gets resolved, every time, in the direction of the fear.
This is what makes the check so destructive. It cannot return a clean result, because attention itself contaminates it. And the contaminated result gets stored as evidence, and the evidence drives more checking.
The same trap in other themes
Exactly the same mechanism runs in sexual orientation OCD, where people check for attraction and find sensation, and in harm OCD, where people check whether they felt anything when they imagined the violent act. In every case the checking produces the thing it was looking for, and in every case the person concludes the worst on the strength of a response the checking created. It is evidence about attention, not about you.
What people find when the checking stops
Part of the CBT with exposure and response prevention work is stopping the check: letting the thought arrive and not turning attention downwards to see what the body did. This is hard, because the check feels like the only way to know. But when it stops, something becomes clear that could never be seen while it was running: the sensations were arriving with the checking, not with the thought. Remove the monitoring and the body goes back to being unremarkable, because it always was.
What I will not do
I will not tell you that the sensation means nothing about you, not because it is untrue but because reassurance is the compulsion, and I would become one more thing to check. What I can do is explain the mechanism, which is reassuring in a way that reassurance is not, because it does not depend on my opinion of you. It depends on how attention and bodies work, and that is the same for everyone.
The rest of the picture
The groinal response is one piece of POCD, and usually the piece that has done the most damage. Around it sits the rest of the cycle: the avoidance of children, the mental reviewing, the reassurance-seeking, the searching for a test. We map all of it and withdraw it gradually, by agreement, and get your ordinary life back. Nothing you describe will shock me, and the first session can go at whatever pace it needs.
If a flicker of sensation has been the thing holding the verdict in place, there is more on how I treat POCD, and this is one of the first things we cover.