Lower back pain

I’ve been having some lower back pain, feels like contractions ( I had them with my first child when I was induced ) but they’re not consistent. And only happen when I walk and sometimes sit down. I’ve been doing a lot of packing because we’re moving into a new house so maybe that’s why. Is it cause for concern to go to the hospital? Or is it just Braxton Hicks? I’ll be 35 weeks on Monday .