1/ Did you disconnect the battery while doing the swap?
2/ If you force reboot the phone, can you see a very dim Apple during the start-up phase?
If you answer 1/No and 2/Yes, you probably damaged the backlight circuit on the logic board. At which point you will need a repair technician with micro soldering tools and skills to fix it for you. Specially that from the looks of it, you caused pry damage to the connector. Were you using a metal tool?
If you do not see anything on the screen during restart, not even a very dim Apple, then you either damaged your screen (try a new known good one) or you damaged the display circuit (different from the backlight circuit) on the logic board. For the latter, a micro soldering technician is also required.
Either way, your first step is to try you screen on a known good phone or a known good screen on your bad phone. Make sure you disconnect the battery first and reconnect it last. And keep all metal tools away. Only use them on screws.