Wendy,
Let's hope for the best and get it biopsied first. We don't know if it's melanoma, so let's wait for the pathology report. I know....it's easy to say "don't worry", but I've been there. Hang in there.
Remember - if it turns out to be the dreaded 'C' word, then its time to educate yourself. This site and The Melanoma Research Foundation (MRF) at http://www.mpip.org are excellent sites to begin with.
Over at MRF, there is a wonderful bulletin board with many members and stories. Please check it out: http://www.mpip.org /bb/bbindex.html.
Good luck.