Thank you for your query at DoctorSpring.com
I understand your concern.
It is not possible to start manifesting symptoms within 2 days even if pregnancy occured. Since she has a histroy of anemia, anemia could have possibly contributed to her fainting.
Also since there was no ejaculation inside her, it rules out the possibility of pregnancy too.
When was her LMP? And when did you have intercourse with her?
Feel free to discuss further,