You may have busted a vein or a hemorrhoid. You do need to figure that out. Many people report using plain stool softeners without laxative. It's basically gut grease.
I have used the 240mg red ones or the little 100mg football types. I have taken up to three or four every time I ate....that was when I was on methadone and high Oxy doses in PM. The nurses told me about it too.
Laxatives that have other ingredients aren't good for long term but plain gut grease in large amounts may help. Good luck and don't let it get away from you. Keep glycerin suppositories too. Insert hours before you feel a turd....grease man, grease!