Hi there and welcome!!!
I think this is so very well done! The proportions are great, I like the way you rendered the hair and the glasses too!
Is this done in pastel? Is it done on a darker surface?
The only suggestion i could offer would be to try and even out the (what I believe is)the surface/paper color showing through, especially on the forehead, nose and cheek area.
This may be somewhat due to the image, so please disregard it that is the case.
Again, i think this is very well done, and for a first portrait attempt, it's outstanding!
Paint the light... it will come!