I know that guinea pigs don't have the muscles to throw up, but it looks as though she is, and she's wheezing when she tries to squeak. I have no idea what's wrong.
Do you have any other information or symptoms?
Is she eating, drinking, pooping etc? How does she seem in herself?
Some piggies cant wheek or lose the ability too.
If however this is abnormal behaviour for her i would get her to the vets ASAP. xx
Please take her to the vets now. Good luck, keeping my fingers crossed xx