Frequent urination and black bloody discharge?

For the past couple of weeks I’ve been having some weird things happen. I’ve had to pee really bad after drinking barely anything and also have what seems to be a constant flow of black (best way to describe it) chunky discharge.

The discharge is kind of hard to explain. It’s like flakes of what I assume is old blood from my uterus? And I know first thought is to say it’s just post period blood, but I’m on the pill to prevent periods and haven’t had one in a couple of months. And usually when I did have that post period discharge, it was more brown and chalky versus black and flaky.

As far as the urination, I really don’t think it’s a uti. I’ve had uti’s before in several different degrees and they have never been like this. Usually a uti is like the burning while peeing, cloudy pee, along with a sensation to pee but not actually going. This is like I pee 3 times over the course of a medium McDonald’s drink. The pee is a healthy color, and it doesn’t burn.

I am experiencing some pain in my back and sides, occasionally around where my kidneys are, so maybe I have some sort of weird kidney infection? But that doesn’t really explain the discharge.

I know nobody here can diagnose me, that’s not what I’m looking for. I just want some ideas of what may be going on. Or if anybody has experienced this and what they had. If nothing resolves soon I will be going to the doctor, but I also can’t really afford the expense so I’d like to see if anybody has thoughts before I take that measure.

TIA!

Ps, in case it’s relevant, it’s impossible for me to be pregnant unless God has chosen his next Mary. I’ve never been pregnant. I am 23 yo. I take combination pill to avoid periods as mine are debilitatingly terrible.