Hi,Glismore

Thanks for posting your query.

Let me explain the basics first.

When ever a man gets turn on, under influence of impulses from brain the ejaculation process starts.The sperm from the testis are ejected in to the urethra that is urine tube.

There are various muscles are present in penis.This muscles contracts and lead to semen being ejaculated from penis.Once this process starts after some stage can not be halted.

This muscle contraction can be felt by individual.In normal circumstances this is a whole process.

As you have said when the stimulation weans off,the process stops in between.This leads to building of some pressure in the entire system.

This minor pressure hurts inform of heaviness and pain at times.

For obvious reasons when the whole process gets completed you are relieved.

This process has got voluntary as well as involuntary components.

I hope this answers your query,I will be available for follow up.

Regards,

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