Do the shoes fit? They shouldn't be tight... and your feet will swell a little while you ride, so there's that. I like my toes to be loose in the toebox.
The stack height of your shoes + cleats + pedals may be different from sneakers + pedals, so take that into account when it comes to setting your seat height.
IT's also very important to get your cleat placement correct because obviously you can't adjust your foot on the pedal anymore. The guidance is usually to put the cleat under the ball of your foot but I'd actually suggest moving it further back than that (just my own opinion)