Scared help!

So I took my daughter in for her 9 month appointment last week and I asked the doctor to check on her hips because hey have been popping when she moves them. You can only feel it not hear it but it had been happening for months but I didn't think anything of it. He wants to do an ultrasound to make sure they're ok and I was wasn't worried until I read up on hip dysplasia and now I'm worried that I did this to her by using a carrier! I chose one specifically because it supported her hips but when she faces forward rather than towards me, it doesn't have the same support. Anybody else babies have normal hip popping?! Google does say it could be just her growing too. I just don't know!