We adopted 2 male Guinea pigs yesterday from a rescue. They were rescued from someone who was going to use them as live snake food 
I've no idea where they came from before that and not sure if it's relevant.
The rescue owner said that they've lived together happily for 3 months and are bonded.
We brought them home yesterday and they don't seem very bonded. One is bigger - he is around 18 months and the smaller one is 10 months. The big one has been chasing, teeth chattering and seems to have nipped (I heard the little one squeal) twice.
The rest of the time they hide in separate houses in their indoor cage. We've had them out twice today for a cuddle and they're friendly enough with us although seem a bit scared.
I've had dogs and cats before but never guinea pigs. I've read that they can try to establish the dominance heirarchy when they move house. When do you think that will settle down? Does this seem like what it is? I contacted the rescue owner and she said it is but I'm just worried the big one will hurt the little one and I don't want them to be scared!
Any advice appreciated!