Ladies help me out!

So currently i am 32 weeks pregnant and having pain in the middle of my back especially when i lay on that particular side.. last pregnancy i had hydronephrosis and it sorta feels like that. I called the dr to tell her and she wants me to go to L&D to monitor the baby.. but it’s not like a urgent right now pain.. it’s been happening for the past couple days. Should i go in?? I feel like she doesn’t really understand what I’m saying