Nail melanoma/splinter hemmorage

I think I am starting to get nail psoriasis as one of my nails over the past few months has begun to get white pockets under the nail, slightly detaching.  One doctor confirmed I most likely have psoriasis on a small patch of my upper leg.  In the past few days I got what I thought was a splinter hemorrhage but after trimming my nail back half way thru the black line I saw that the black line was on my nail matrix.  Is this just from the blood vessels under the bed or should I be worried?  I have an appointment for a dermatologist in a month for something else but should I get this checked out sooner?

Thanks