Straining to pass gas 3 weeks after csection

I'm 3 weeks pp and in the last couple of days I've noticed a change in my bowel movements. I only know I need to go poop because I get sudden back pains where my epidural was given. And passing gas is a mission. I get the urge to pass gas but I can't without literally forcing it out. I feel like how I did when I just got out of csection. Anyone know what it could be?