I have PCOS and I have very irregular cycles. But, when I do ovulate (which is probably once every 2-3 months), I go through a "normal" relatively painless cycle - normal AF lasts for 7 days, bleeding is within normal amounts. With Endo, you may have the normal monthly cycles, but the lining of the uterus builds up on other areas of your abdomen, causing severe pain and discomfort for most women, including increased bleeding, heavier, with clots and lots of cramping.

Either one isn't pleasant to have, having both together must be horrible
I am the same as Blackrose. My main concern was my lack of regularity. I actually had fairly good periods when they came. Went to the GP and she did a blood test and sent me for an ultrasound. Bloods came back "normal" but the scan showed the typical PCOS pattern. Apparently to be diagnosed (according to the gyno i then went to) you have to have 2 of the 3 symptoms: ie. 2 of the following:
1. Irregular periods
2. Typical PCOS patterned ovaries
3. Abnormal hormone levels.

Other friends of mine who have bad PCOS also have the unexplained weight gain, and hard to control weight, also excess bodily hair growth etc. They also have crazy bad periods or bad ovulation pains.

Cant help with the endo though sorry. I think go to your GP and they can get you checked and then you can work out what your are dealing with ATB!