BACK LABOR?

I am 34 weeks pregnant with my 5th baby & have been induced 3/4 of the times so I only went into labor on my own ONCE. I just had steroid shots to help baby’s lungs bcuz the doctor has a feeling she will come early. ANYWAYS. I keep having this shooting pain go straight across my back along with pressure around my stomach & I assume these are some kind of contraction. PAINFUL & take my breath away but I can still breath through them. Anybody else experiencing this?