Just had a wierd handling, she kept opening her mouth

I was handling my baby snake today and she was super sluggish and not even flighty to pick up, for a few minutes she was super chill just hanging out, then she started opening her mouth up all the way and just leaving it open, and looked like she was constricting her stomoch area (nothng there, last fed her Sunday night), no idea what this could mean. She did it for about 5 min until I put her back in after 15 min of handling cause dinner was ready before I expected. I did get a little bit of video I can post shortly.