Oh this is very sad. I'm sorry you can't get to the vet. Don't try and give her any ibuprofen - although I appreciate you feel desperate it can do more harm than good if you get the dose wrong and the last thing we need if for her guts to be damaged and for her to stop eating anything. If she has internal bleeding or organ damage there won't be too much a vet can do - it will be pot luck. Any anaesthetic is quite a risk for little pigs so it's not like us big people where we can just be put under so the doc can open us up and have a rummage to see what's wrong. Just try and make her comfortable for now in her own house.
Piggy will be feeling frightened all the time so it's important that she feels as safe as she can. Is the cage on the floor? Perhaps it could be raised onto a table at least until she can recover a bit. Any maybe cover it in the most part with a blanket for a while so she can burrow into a hay-filled box or a snuggle tunnel in there to doubly hide and feel a bit safer. One of the problems when you have a lone piggy is that she cannot look to her friend for comfort and guidance on how to behave so she goes a bit crazy because she does not know what to do.
My pigs are floor level and so I do not allow dogs into my house at all. It will be safer if you ban the dog from the room piggy is in (maybe she's in your bedroom?) as any time piggy senses the dog now she will stress out, and your dog will find her very tempting. Some types of dog have a very strong prey instinct and we just can't over-ride all that nature by telling them off. If the worst was to happen, and your dog hurt your piggy, you'd never get over it and it would be very hard for you to feel the same way about your dog again. We can love our dogs and cats by respecting that they are predators by nature and no matter how many videos are online with dogs licking guinea-pigs (
) they should be kept apart for safety. As you unfortunately found out, it only takes once. Your little girl is still with us and still has a chance. There have been a lot of sad posts in the past from people who haven't been so lucky. So make her comfy, raise her cage out of the dog's reach and let her settle in the quiet with a blanket over her sturdy cage, and give some tasty hay, a little bit of veggie and some water to drink. If you have a safe sort of heat-pad that can keep her warm but not to hot I'm sure she'd appreciate that. We'll be praying for her recovery x