first of all, you DON T immediatly know if the morning after pill works. The signs of either getting a period (LIKELY to be a bit different than normal.. more or less amount more or less cramps, often stuttering flow) OR not getting a period. It is about 90% effective AND you are about 90% NOT likely to need it ! So, your odds of pregnancy are only about 1 in 100. On the other hand, there s a 100% chance that taking a huge jolt of female hormones will change hormonal tone and menstrual cycle. The abdominal pain is worrisome. That occurs with the menstrual cycle, and if she has menstrual pain and menstrual bleeding, then, that is about expected. Pain without the cycle... something else is going on and needs to be looked at (although serious problems are uncommon they are not rare; mostly they would be coincidental, like an infection or a stomach flu or a UTI.. if also pain on urination then that s the situation). Which brings up the vaginal discharge. Some discharge after intercourse is 100% and this is the type you would get. Doesn t have to be abnormal BUT the pain implies a potential (treatable) infection. Pain and discharge goes away, could be an STD.. unlikely. Pain and discharge stays... big problem. Pain turns into a normal period.. oh... not so much a problem.