Is my robo dwarf hamster pregnant?

my girl roborovski dwarf hamster, bon bon, is she pregnant? i put her with my males 13 days ago and about a week after i put her with the males again and everyday since then, shes gotten more aggressive to them and sometimes when passing them attacks them and tries to get out there cage ( digs the glass and runs around like mad ) she has gotten a bit more heavy ( could be due to growing ) and a bit slower but a bit more acive ( kept me awake last night "digging" the glass ) and somewhat drinks more ( could be due to its summer now and its getting hotter )