Seven Month Old Splinter

I have a foreign object embedded in the lower part of my right thumb,
plam-side. It's been there for a few months. I have no idea what it
is, but when I first noticed it some months back I tried to remove it
with (steralized) needle, tweezers, and manicure scissors, with no
obvious luck. After a few tries, I just left it alone and forgot about
it. Now, about seven months later, the area over the skin is beggining
to itch, and I can clearly see the object, not far from the surface. I
want to try to take it out again, but am afraid of harming myself. Any
suggestions?

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