Plz help. What could it be?

I found out I have group b strep. I had antibiotics for it. I finished it and I felt like after I finished the medicine that I have a severe uti like terrible pain. And I went to the dr they ran urine and I have no infections or anything. I’m 15 weeks, they kinda just sent me off like no big deal. But then if nothing is wrong what’s causing the severe burning and uncomfortable pain when I go to the bathroom? I feel like something more is going on and the dr isn’t even caring at all to listen.