It is at least plausible, that you could run an AC current over your arms and over your chest. This can cause a stimulus to your nervous system if the current is high enough to overcome the action potential.

A tingling sensation, muscle spasm and aching would be the cause for low levels of current and prolonged exposition.

But since you found the culprit, you would be easily be able to mitigate your exposure. Either by wearing latex or rubber gloves or proper grounding of your device, which should not shock you btw.

Above the action potential you muscles will contract and your nerves will give stimuli, which can cause tension and anxiety.

If you feel the shock sometimes you are definitely above action potential.

There is another threshold above the action potential, which will cause irreversible damage, heart failure or death. A residual current device is usually installed with your circuit breakers to prevent residual current above this threshold.