is this mole cancerous?

Why not try your own doctor? I don't mean to be rude but how could expect anyone to give you a worthwhile answer? Firstly, there are no doctors here.
Secondly, any ethical doctor on any forum would NEVER advise you sight unseen.

If you have such a serious concern such a potential skin cancer, make an appointment with a doctor.

how do I add a picture?

Even if you added a picture, I still agree with Ragman. Even a doctor, with years of experience, and an educated guess, would not definitely say that a mole is benign or cancerous until he has had a biopsy done.

http://able2know.org/about/tos/

Look up the websites of your local skin cancer centers and ask them when they will next have free skin cancer screening clinics.

That's what I did after moving to NM and found that I had several basal cell skin cancers. The screening didn't cost me anything and was well worth the waiting time.

Until you find someone local who can check it out, here's a link to the Skin Cancer Foundation's Annual Bus Tour schedule. They travel all over the country doing free screenings:

http://www.skincancer.org/events/tour

The sooner you get it looked at, the less anxiety you will generate about it.