Wide urethra

I tried self-locking today. To give you the gist, I was affected by an ED medication (the short version: I can get hard fine, but my partner frequently takes meds that delay her orgasm significantly, and if we go past a certain point, I sometimes lose my erection).

While watching some of my favorite porn, I really pushed against the cage. When I looked inside, my urethral opening appeared quite wide open; I suspect it was because my glans was straining to break free from the confinement. It had a slightly odd appearance at first, but shifting things around made it look more standard.

Has anyone else experienced this?