Scared Guinea Pig

Question
I got my guinea pig today from a pet shop. He is a crested piggie and i have a friend for him aswell. Our cage is 2 tiers so i put one on top and one on the bottom. Ginger (on top) acted scared for a longer period of time than Biscuit. Eventually he let me pet him and he ate from my hand. Then we tried to put Biscuit in the same level as him for company but they didn't seem to like it so w3e split them up. He has acted weird ever since, he won't let my touch him and he keeps jumping away suddenly. I am worried now as he seemed happy as anything before but now he is just sitting in his cardboard tube and won't let me interact at all.

Answer
for the most part it is dominence behaviour, the more they are forced to see each other the more used they will get to one another, i would avoid housing them together at least for the time being but at least keeping them in a place where they can see and maybe sniff each other. a good tip is to alternate their homes, this helps mix up the scents without the risk of them fighting. over time (a few weeks) you can then try the pair together in neutral territory like a play run.

once you have got to this stage please contact me if things dont go well with the introduction.