Have severe backpain and in bowels when trying to stand straight. Taking ibuprofen. What to do?

I have no idea what has happened but I cannot stand up straight and if I try I get to a certain point and it sends shooting pains round my lower back that are so powerful if feels like Iv got an ache in my bowels as well. I have taken ibuprofen and tried to stretch out flat on the floor which resulted in me having to get someone to help me back up. I cannot get an appointment at my doctors today as they are full but I need help as I am in agony just sitting. When I walk I'm having to walk slowly and bent slightly forward as this is the least painful way to move around however walking like this is making the top of my back ache and my legs wobble. Please help