I'll tell you something that I'm hoping might help.
When we adopted a sow last year she came to us bloated, the rescue never took her to get this checked, my son did though and the vet tried to say it was nothing.. anyway as time went on we noticed blood in the cage on and off, we couldn't pin point which is was because we had 4 sows in total but we did split them to try and see if we could find which one was doing it, but nope. Anyway we moved here in February and I noticed Badger was snapping at her sisters but never thought anything of it because she was still eating, then one day I asked my son to get her out because I wanted to hold her for a bit (something was telling me to hold her), he got her out and she was freezing cold, tired, in pain, I asked my son to call the vet and he took her that same day, sadly she had lost 200kg we didn't notice because she was so bloated, her organs had began to shut down, so we opted to have her put to sleep. Please don't let your guinea pig get like this because it will make you feel worse.
Also we had the little piggie pts in my profile picture about 4 weeks ago which was really hard for us, but I didn't want to see him suffer.
I hope you call the vets and get some advice.