I Have Pelvic Pain On Right Side Only, What Could It Be?

Depending on the side.  I believe your appendix is on that side.  If the pain becomes really bad, get it looked at by a doctor or go to the hospital.  At least maybe call a nurse.  You don't want your appendix to burst.
Also, pelvic pain can be caused by several things.  You may have an onset of endometriosis.  Which is extremely painful, and you cant do much about.  There are many reasons, I would get it checked on by your doctor to out rule anything serious.  Good luck.

You should go to the hospital as soon as you can, the appendix is on the right side, and it doesn't take long to make you very ill if it ruptures. If you develop a sudden fever and a large amount of pain on that side, I would call an ambulance. Hope this helps, good luck to you.

It could be numerous things, but yes, the appendix is situated on that side.

Do you have other symptoms?

I would go to the doctor for a check up. If it is the appendix, he can make a more educated diagnosis.

Try not to stress too much before you go. But go as soon as possible, just for peace of mind.

Hope you feel better soon.