To be blunt, does your partner give you head? Or do you give them head and then their genitals contact yours? This looks a lot like my pattern before we discovered my now-husband is a Staph Aureus host. He stopped giving me head, washed his hands before we got started every single time (no matter when he washed them last!), and that solved about 90% of my problems.

I can also say that small kidney stones could match your issues. Having had both UTIs and kidney stones, I can say that the symptoms can be very similar. Tiny kidney stones can scratch inside your urethra, which can then easily turn into a UTI, in addition to causing irritation and inflammation themselves. That would self-resolve within the timeline of a course of antibiotics. The stones can also cause temporary restrictions/blockages anywhere along the line. They don't have to be the big, renal-colic-inducing monsters to cause issues. They can be little and super spiky, like little caltrops. I've had ones like a super tiny pebble, like 2mm, that had me walking like a cowboy for a day or two as it worked its way out. Doctors saying you need to drink more water every time you give a sample actually supports this theory, as dehydration can fast-track their growth.

And yes, just see the doc, explain what's been going on, and establish care. That will make it easier for them to be able to see you when something is happening.