I'm worried I might have some issue with this. If you have it, please, let me know:

How strong the stimulus has to be to cause it?
How long does it have to last to cause the pain?
How often do you have it?

I avoid jerking off in days I'm aware I'll get laid (I have a mildly bad time with condoms), in these days if I get stuck in hot make outs or foreplay for anything close to an hour things start to get bad.
If I jerked off it'll have to be twice as long, so it basically won't happen.