I am feeling a pressure similar to what you are describing... Didn't have it with Charlotte... But she was prosterior and the way I am carrying this tme around, bubs is anterior, is completely different and the pressure has been pretty constant. I attribute it to the way she is facing.
The other pain does sound like sciatica. How is your bum cheek? lol First time around it was my bum cheek and outside hip, down the back of my leg and into my calf. There are some exercises you can do to help ease it, you should be able to google it for some.
IT could be a UTI.
It could also be baby's head (or something else) pressing down there, though you're maybe a bit early for that? I've been getting the same thing in the past week or so and baby's head is just at the top of the pelvis, so I guess squashing my bladder a bit. It's bloody annoying.
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