Smelly discharge after sex

iL
Okay, so this is completely and utterly nasty, but I have a weird question.... 
ALMOST everytime my husband comes without pulling out, I walk around the next day smelling like freaking fish?! Like what the heck?!
Any other time, I NEVER smell funky and after about two days I smell normal again. 
No itching or anything unusual..
His gizz never stinks, not until it mixes with my stuff I guess... but I CANT comprehend what's going on here. 
Does anyone else have this issue? Or know what the heck is going on? 
PLEASE TELL ME IM NOT ALONE