I have two rats they're both around 5 months old and I've had them for a month or so maybe a little more...they're both not very affectionate rats but the smaller one is the least. He's skittish, he doesn't like me touching him and sometimes he pushes me away with his nose or paw or just runs away. Very uninterested it seems like he doesn't like me at all! Do you think they'll change over time??