Right Lower Abdominal Pain: Causes & Possible Explanations

Question
this pain on my right lower abdomen has been present for two days now. what is the cause and this is the 18th day of my cycle.

Answer
Since you are in the middle of your cycle, it is probable that the pain you are feeling is ovulation pain, also known as Mittelschmerz.  This is not uncommon.  Some women can even tell which ovary they are ovulating from each month, and pinpoint ovulation to the day.  Others may only feel it occasionally.

If the pain continues or worsens, definitely get it checked out by a doctor.