Could Light Periods Be Due To Endometriosis?

Hi, I'm a 33 year old female with history of endometriosis and ovarian cysts. I have my period right now, and usually always have a very heavy cycle. I had tremendous pain on my right side on Tuesday, and continue to still have shooting pain. I don't have an appendix. Just wondering, why I would have a super light period. Could it have something to do with endometriosis? is this common?