I switched baby formulas on my almost 3 month old. Unfortunately, she is extremely constipated. She screams everytime she tries to poo, and only manages to squeeze out a little pellat. It’s heart wrenching. :( Is it possible that it’s just the switch of formula’s, or is it most likely the new formula? I would jump back to the old formula in a heart beat, but I’m afraid that if it’s the switch, and I switch it again, I’ll have her little belly all messed up. Please help!