Nipple/areola Change

I'm currently 22 weeks pregnant (28 years old) and have noticed for the past 2-3 months that one of my nipples has changed color.  It's more yellow and the areola seems to be much thicker than my "normal" nipple.  The little "bumpies" that appear on my normal nipple are actually inverted on this affected nipple as well.  There is no discharge, no redness, no noticable lumps, and it's not tender to touch.  This is my second pregnancy, I breastfed my first child (that was 5 years ago).  Is this something I should be concerned about?  I just had surgery in April 2008 to remove melanoma from my shoulder ... and I'm trying not to be paranoid but I can't find much information about color and texture changes for nipples/areolas.

BE PARANOID! Go see your doctor.

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