Good afternoon, see by the history you have given and the photo you have shared it's difficult to give any diagnosis here. And also here we don't know since how many days it has started, is it increasing in size, is it painful, any discharge is coming from that, etc.
So it's better for you if you consult an General surgeon in your area and do the investigations prescribed by the doctor.
Next Steps
kindly consult a general surgeon as soon as possible.