Advice needed! Have I dropped?

I'm only 33 weeks 3 days, but in the last few days I feel like my baby may have dropped. It's much easier to breathe, I've had increased pelvic pressure/pain, back pain, increased Braxton hicks, and I can feel her kicking lower on my stomach. But I don't see a difference in pictures. I'm already at risk for preterm labor and didn't know if I should be worried (with my others I dropped 3 weeks before I had each baby which would still be fairly early).Thoughts?