Good evening, Nausea and stomach aches can be side effects of the morning-after pill, but they usually do not last more than two days. It is possible that your symptoms are not related to the medication, such as if you are developing gastroenteritis. Stress from the events may also be contributing to your symptoms. Additionally, your cycle may be delayed somewhat by taking the morning-after pill, but you do not need to worry about this. Please write back in a few days to let me know if your symptoms have disappeared. It would be surprising if your more intense pre-menstrual and menstrual syndromes were caused by taking the morning-after pill, but it is not impossible. We will know for sure if your next menstrual cycle is much less painful. If this is the case, then we could think that this "bad patch" was caused by the morning-after pill. We look forward to hearing from you.