One of my guinea pigs started acting weird today. She was standing in one spot and started to hop, but it wasn't the same jumps when she popcorns and it was only her back feet. Also, my best friend and I tried to get her to respond and she wouldn't. We were tapping in the cage and poking her; she just continued to look forward like she was fixated on something. I'm just really worried that something might be wrong.