Warum setzt der Menstruationszyklus meiner Frau bereits nach 3 Tagen wieder ein?

A woman could be pregnant if she gets a menstrual cycle after having sex for 11 days, but other times, this is not the reason behind it. You can see cramps in this regard or some bleeding that is not typical of a period. This may be due to the changes in your hormones, or there may be other issues that have lead to this. To diagnose the situation, it's advisable to take the pregnancy test a few weeks after the last time you had sex. Although it's not necessary to have periods after 11 days each month of the sexual act, it does occur sometimes, but it's not always indicative of pregnancy. 

Without a physical examination, it is hard to really determine the reason. For this reason, you should be referred to a gynecologist who can perform a detailed check and can prescribe you medications

Taking Unwanted 72 after unprotected sex can help in case of pregnancy. It might have to be mentioned that young people should take it within 72 hours. Since the usual menstruation time has passed and in the meantime, you've already got your period, the symptoms you may develop are mostly related to the bleeding. Spotting or changes in the menstrual cycle are the main issues after taking the pill. 

Yes but only if it's detected early but a close monitor is necessary. But talk to your doctor whether your overall health condition permits it or not

White and itchy vaginal and anal areas indicate Fungal infection . Scratching causes scars. Consult a doctor for diagnosis.. Over the counter antifungal creams may temporarily relieve symptoms. AVOID tight clothing and keep the area Dry.