Hello After A Night Out Of Heavy Drinking I Went

Hello after a night out of heavy drinking I went to the toilet and a mini explosion happened with black stools but also large clumps of what looked like blood clots. My stomach has been sore ever since and I've felt sick the whole time. I have taken some ompeprazole but this hasn't worked my question is is this serious as I am supposed to be back to work today and can't afford to take time off. Thanks ever so much