Some women's feet get bigger during pregnancy and stay that way, some get bigger and go back to their previous size afterwards, and some don't change at all. It is almost impossible to say which you might be.
My feet went up during pregnancy, but didn't stay that much bigger afterwards. I permanently went up about 1/4 to 1/2 a size, which just makes it harder to shoe shop because I need to buy some shoes bigger and some the same size. I was probably a full size up for a good 6 months after delivery, and then my feet started getting closer to pre-pg size again.
So you may be in flux as far as shoe sizes for for a while!