My Girlfriend Is Having Weird Cramps Around Her Belly, We

my girlfriend is having weird cramps around her belly, we thought that it might be her period( her period is due to tommorow) but she said that this time it hurts differently, not like her usual period pain. she said its around her belly. But were not sure yet because her period is due tommorow. we had sex like 2 weeks ago. could this be pregnancy