Crampy lower belly / back pain? What is it?!

I am almost 27 weeks. In the middle of the night, I noticed that I felt very slightly crampy in my lower belly and on the sides. Barely noticeable, but still uncomfortable.

Now it’s the morning and it still feels the same, but is now mostly in my right side (lower) and feels like it’s spreading around to my lower back on that side as well? Almost around my hip area?

It’s a pretty constant feeling, and there doesn’t seem to be any uterus tightening that I can feel. Baby is moving like normal. No weird discharge or anything. It feels the same regardless of how I’m laying.

I did walk around a zoo yesterday and had some very slight back discomfort from walking a lot.

Anyone had a similar experience? Should I be concerned it’s something else?