Is this sciatic pain?

I’m 25 weeks with my second and I don’t remember having this type of pain when I was pregnant with my first. Essentially I’m finding that if I do anything for long periods of time (standing too long, sitting down too long, even laying down in the same position for too long) my lower back into my butt cheeks becomes very sore, especially on my left side. I also feel like I’m having pelvic pain a lot more than I did with my first. This baby feels very low (my first never really dropped and actually was breech) but this time it just feels different. Is this sciatic pain or something else? I do have a belly band and haven’t been the best at wearing it (I truthfully forget) but I’m hoping if I wear it more that will alleviate some of the pain…it’s getting to the point where sometimes it really does hurt to walk without a limp. My next appt isn’t until next week but I just wanted to see if others experienced this pain too, thanks!