Baby burping? randomly

Hi,

The last few days my 7 month old baby has been making sounds like the stomach content is going into her throat and then she's swallowing it back, or kind of like doing burp sounds, two times she vomited it out. She doesn't seem to be bothered by it at all.

Anyone had the same experience? I don't want to take her to the doctor if it's not an issue. I mean she seems fine, I'm thinking it's maybe because she's more mobile and making herself sick? Is that possible? But it's also worrying me.

Additional info:

We also missed a day of solids when i started noticing it started, but she's also tried something new (avocado) the day before, so I skipped few days if that's somehow caused by anything she ate - no changes. And considering she has barely eaten anything before, I don't feel like not eating solids is causing this either. I haven't changed my diet either, I'm breastfeeding. She's had reflux as a newborn, but hasn't had issues for months.