Should my bone graft be visible? (Photo)

I had a a bottom left tooth extracted #18 I believe. I had it done about 3 weeks ago and I'm in no pain without any swelling. The last couple of days I noticed what appeared to be some of the graft visible. After some research I've seen that having some of it visible is normal but a lot is not. I would just like to know if I have to much poking through my gum or if it is healing correctly I'm paranoid. Once again I have no pain whatsoever just the visible graft. Thank you to all in Advance.