Last time my gril friend'd period time is very hard then I admitted to hospital and the doctor gave Saline and some medicine. Her next period date is 22nd of February 2010. I had sex with her on 13th of February bu using pull out method.I'm sure sperm was not gone inside. My girl friend has not get period time yet. I'm scared. How can I know the period stopped due to last time medicine or other cause? Please reply me