I'm 21 years old and attended a party one night during which there was considerable consumption of alcohol (5-6 glasses); upon returning home I had a snack and fell asleep for 6 hours. In the morning I took a Tylenol ER pill, drank juice, and had two sandwiches. As the day went on, I began to experience some discomfort in my stomach and some fatigue. This has been ongoing for 3 days now, with the addition of a mild headache and not being particularly hungry, except mildly every now and then. Could it be a flu of sorts or something more serious?