A few days ago I noticed one black 'mole' on my labia minora (I wiped and it felt more raised which caused me to investigate further). I pinched it and blood came out so I thought it was some kind of friction blood blister?. I've looked again today and the black spot is still there and there are a few other smaller patches near it. 
 

I'm worrying that there is more to it than just a mole. Has anyone had a similar experience or can offer reassurance?

I do have photos (which don't show too much!) but I can't find a way to post this with the attachment?