I've Been Having Protected Sex The Past 2 Weeks, Probably

I've been having protected sex the past 2 weeks, probably 3-6 times during those weeks. My girlfriend just finished her period when we started doing it. She had her period just now, a week earlier than her expected date. It was a strong period (had to change her pad 3 times the whole day) but it only lasted for a day, she then had yellowish-white liquid afterwards that lasted another day. What are the chances of her being pregnant? Her expected period is due 3-5 days from now. Thank you.