LOL! Yes, your hamster must be a girl, usually when they are ready to mate when you touch their back they stand still and their tale goes up, it will stay fixed in this position until they think mating is finished or you stop touching her. Our hamster does the same thing about every three or so days according to her cycle of fertility. Its about the only time I can really pat her without her running away. Don't worry its her natural instinct to do this, your not hurting her. Unless you make her stay like this for a long time.
