Hey ladies! So I need some help!

Okay so for a couple of days my back has been hurting right under my ribs and when I pee sometimes it feels (this doesn't happen all the time) like a sword was stabbing me. I am pretty sure it isn't a uti since they usually burn. I called my brother since he had kidney stones and he said it could be a kidney infection or small kidney stones. But he can't help because he isn't a girl😂😒 I had sex last night with my so (we are trying for a baby) and this morning I had stringy white discharge. I have never had this. We have been trying for four months now. Tomorrow I am suppose to start my period but my cramps feel way stronger than usual. I have been feeling nausea every couple of days or real warm and that what makes me think it could be a kidney infection or stones. What do you guys think? I can't go to the doctor until Sept 1.

Oh, and for a week I have been having small amount of white discharge it almost looks like cream rinse. But I just figured my period is about to start.