Is there a limit to Physical Pain a Human body can Sense?

The answer is yes, There is some limit which human body can Sense the pain beyond which pain doesn't exists. The action potentials spiking goes from -70 mV to +40 mV and then there is the refractory period of some nS to 1 mS where it's a inactive state, spiking of neurons is about type of pain and how long the pain is there is frequency the pain has.

This article is regarding the amplitude, there are different sensitive regions in human body and considering the pain with cut should be the same and based on the sensitivity of the body part there is a variation in pain. Hence there is a limit to the pain a human body can understand as Neuron spiking cannot exceed +40 mV and since there a limit on spiking itself how can a sensation i.e. pain go beyond a limit?

There is definitely a limit which is not yet found in terms of units but pain cannot be indefinite in strength.