Flank Pain/Stomach

I’m 33 weeks 4 days. Recently anytime I have to pee my stomach gets really hard and uncomfortable very low down, a little painful even. For the past 2 days I have had flank pain on both sides that comes and goes, sometimes it’s sharp sometimes it’s more achy. Of course, my back aches as well. I have also had a hard time walking, my hips and pelvic area hurt so bad, especially to spread my legs even just a little. Is anyone else experiencing this? I don’t have burning when I pee. I did have Hydronephrosis (swelling of kidney) on the right side at 18 weeks, they suspect it was baby putting pressure on my ureter and i do have a history of kidney stones. I have an appointment on the 1st but want opinions in the meantime?