Maternity Leggings painful experience

I bought some Maternity Leggins from Walmart saw it said exercise maternity leggins but didn’t think anything of it wore them one day a couple hours by end of day I was so sore like I had worked out my lower stomach was so sore. It hurt to walk or go from sitting to standing. & the soreness continued into the next day. I ended up realizing the leggings must have worked like shape wear or something they felt fine while wearing them but slowly the soreness creeped in. I have tons of pregnancy leggings so will stick to those & donate these 😅 I was so worried but by the time I got in touch with my OB the pain had completely gone away as I took off the leggings & mid day the next day I was much better & by the 3rd day perfectly fine. Just thought it was silly leggings caused that. I’m I was exactly 26 weeks the day I put the leggings on.