why and when does your penis shrink
 

My husband has always had a problem with his penis shrivelling when he gets nervous, worried, or is in cold water or cold weather and his balls disappear in the same situations, I wondered if this was a common complaint or is it just my husband, he doesn't have much to shrivel to start with but in these situations it becomes almost invisible as do his balls

I’m assuming you husband is bigger guy? Because my penis is normally shriveled up since it’s not very big to begin with also.

Yeah, cold (air or water) shrivels me up. I also shrink back when naked in front of others, like when I'm at a naturist beach. This is fine by me because there's no embarrassing hard-ons (though that would be a miracle) and I get off on the SPH thing...

All of the above mentioned scenarios cause me to catch an "innie" as well. Also, physical exertion, like hard exercise. I've got nothing showing when i head to the locker room to shower. :(

Yes that as well. Thinking back to my wanderings around naturist beaches, I'm pretty sure that when walking about, if you are above a certain size, your dick swings or flops back and forth on your thighs, which helps to keep it stretched out. Below a certain size, I'm convinced that walking has the opposite effect and serves to push it in.

I know what you mean, but i thought that was a purely psychological thing. Like, us little guys are scared and intimidated to be exposed. But the big guys feel emboldened and cocksure. Pun very intended.

Well, that could be. I like to be exposed (in an anonymous environment) and I like SPH, so maybe the shrinkage is my body meeting that need. There was a time when trying not to bone was a problem - but not any more...