Thanks for choosing health care magic for posting your query.
I have gone through your question in detail and I can understand what you are going through.
Most probably it could be a bruise
or a inflammation that has occurred cause of trauma. Most probably in 5-6 days it will resolve by self. However if the symptoms persist then you should see a doctor who will need to examine the lesion. You may take tab paracetamol
for pain if the pain is troubling you untill you see a doctor.
And next time be careful while you drink alcohol.
Hope I am able to answer your concerns.
If you have any further query, I would be glad to help you.
In future if you wish to contact me directly, you can use the below mentioned link:
Wish you good health,
Dr. Srikanth Reddy M.D.