Surely this is just a story, but just in case you're actually concerned: SALT.
Your jizz has salt in it. Plants and aquatic animals don't do well when you suddenly add a bunch of salt to their environment. As for your dog and girlfriend you were too vague to be certain but I have a hunch those were unfortunate coincidences.
Yeah no he's cursed you need to go to egypt
Even if this is real, just lower your salt intake or just don't cum in your girlfriends. And why the fuck would you ejaculate into a potted plant? And I'm pretty sure the dog ran away because it didn't want to be jizzed on and got hit by a car. Ridiculous.