Thanks for posting your query at DoctorSpring.com. I can understand your concern.
It seems to be quite severe, it is a bacterial infection which might have started out as a furuncle but seems to have turned into an abscess. It could also be a std. Most of the stds are caused due to bacteria.
I would recommend a visit to your doctor as soon as possible. The abscess needs to be treated actively by your doctor. Also you can request your doctor to ask for investigations to rule out std.
Application of betadine cream will not suffice and the antibiotics you are taking might need to be given in a higher dose.
Please let me know if you have any queries.
Patient replied :
Thanks for the reply, it answered many of my concerns. I have just one more question.
The "boil" has gotten quite smaller over the past 18 hours. What will happen if I just leave it alone, will it drain itself?
Thanks for your reply.
It would be difficult to say whether it will drain itself and looking at the picture, my opinion was to visit your doctor, an abscess might lead to severe inflammation and swelling of the surrounding tissue too, hence it's important to get it treated immediately.