One if you have menses after having sex and even there is full penetration and ejaculation, there is no chance of being pregnant.
I mean to say that if you have a normal menses after the sex at your normal time than chances of pregnancy
is very rare and not possible.
In your condition which you have describe there is very rare possibility of any thing from your booyfriend being gone into you and the chances of being pregnant is very very less and other important thing which make this confirm is that you have your normal menses after one week of this which make it impossible for pregnancy. Once menses is there the uterine formation which is there for maintaining the pregnacy is washed off and there is no possibility for any implantation
to being pregnant.
Thanks and take care.