I think my chinchilla might be pregnant

I bought what I thought were 2 male chinchillas, but now I'm not sure, due to the fact that one of the chinchillas is spending a lot of time in the nesting box and also it has been dragging newspaper and shavings into the nesting box, the other chinchilla will sit on the top of the nesting box, and then goes away. Then after a while, it will go back onto the top of the nesting box, as if it is checking up on the other chinchilla.
Asked Mar 28, 2015

TIP: If it's not your answer to this question, please click "Leave a Comment" button under the question to communicate with the question owner.