A lot of risk. 2 Weeks before your period is most likely your most fertile time. He will ejaculate less the second time and even less the third time but there is still plenty of sperm in his ejaculate.

Get Plan B if you have any doubts. Also get some condoms while you are there. Pull-out is not a safe way for birth control and you are exposed to STDs and STIs without a condom.

The pull out method is actually not a method at all. You can get pregnant when he "pre-cums" which will happen long before he truly ejaculates. So there is quite a bit of risk. So I suggest you do what susan suggested and get Plan B, Also look into getting on Birth control and make sure you use a condom whenever you have sex.