Hello, I am a healthy (I hope!) 26 year old woman who has recently gone to the doctors regarding a mole on my arm which I have had since I was a little girl. perhaps even from birth. 

I caught the mole when changing around 6 months ago, and the mole was sore for a little bit, bled a tiny amount and then healed fine. 

Around a week ago, I noticed that where the mole has healed over, it has appeared to form a small lump on the upper left part of the mole, similar to the appearance of a skin tag on top of the mole. 

I went to the doctor three days ago, and they took a picture on a phone camera to send to the teledermatologist. They said I should hear back from them within 2-3 weeks whether to come in for a biopsy or monitor it for further changes. They said it doesn't look like anything to worry about - but mentioned it did look a slightly different colour - but this could be a scab from where I'm potentially catching the mole.

I have quite severe anxiety, and when everything else is my life is going well, my mind latches onto the worst such as melanoma. Even though I know the chances are tiny, I still keep worrying.

I wanted to reach out to firstly find out if it's common for a mole to grow back weirdly after catching it / if a mole can grow as you age and still be benign ? (I appreciate you can't definitively say if it's ok - I am just looking for some comfort with best case scenarios I suppose).

Also, if the dermatologist comes back saying it looks fine and to monitor it, am I allowed to politely request a second opinion and push for it to be biopsied ? I don't want to be demanding or rude, but I just feel if I don't have it biopsied, with my health anxiety this worry won't go away... as I know a picture cannot rule everything out. 

Sorry for the ridiculously long message. I really appreciate any advice or support you can give me !