I usually ejaculate while laying on my back and the orgasm is average, however, sometimes I lay on my side which allows me to massage the lower region of my testicles and sometimes (not everytime) I get some sort of “afterglow” a type of post orgasm that starts on my belly buttom and spreads to my genitals, it’s a lot stronger and more satisfaying than the original orgasm and most times I even ejaculate more.
I don’t know what causes it since I can’t get it right everytime but if anyone has experiences this or knows why it happens I’d love to hear about it.