you did the right thing to let it air dry....what I would do instead of washing it twice a month invest in a nice duvet cover for it and wash that instead
They'll be fine. You could sew the shams if they look too big. Sew a 1" seam on one long side and one short end. If there is a pattern on the shams that you want to keep in the center of the shams then sew a 1/2" seam on the two long sides and 1/2" s...
i agree with the 1st answer. this site might help