Unfortunately I know nothing of WordPress as I use Microsoft Word.

As for the shard of glass, have you tried a needle? Whenever I get a splinter/sliver from dance that's too small for tweezers, I just stick in a needle and swirl it around and make a bigger hole for it to come out....it is terribly disgusting but less so then if it were to get infected which is not a pleasant sight.

I suggest the needle cause glass carries all sorts of bacteria...Good luck!