Wow it sounds like you're really enjoying all your sexual experiences with this person & going slow so you're both comfortable. That's awesome!

Sometimes I do have that feeling during sex that I have to urinate eventho I go before we start. My problem is I have a weak bladder from carrying children, but I've also read & experienced many times "squirting" & it is the feeling that I have to go. If I hold it, it becomes painful. So my partner told me to push with the urge & sometimes this causes me to squirt which, for me is a different type of orgasm I feel in my pelvis, groan & works up into my chest area. At first it scared me bec I never experienced it before, but for me it is a type of body orgasm that I have. Totally different from other types of orgasms that I experience.

Now when this happened I was at first very embarrassed about it bec some say it's urine & some say it's not. That's a different argument, but it does not embarrass me anymore & my partner enjoys it too. So I think with time you can learn to relax & enjoy this more.

Have you tried different size & width dildos? It might change the experience too.
All the best to you & have a blast!