New retainers hurt like hell despite fitting perfectly

About a week ago i got new retainers, and theyve been hurting my teeth like crazy. Idk what to do, I've been wearing them as much as I can. I literally cant fall asleep with them because after 15 to 20 minutes it feels like my teeth are screaming at me, and its getting to the point where it starts to feel like this even when I'm not wearing them. I tried melatonin before bed and that barely helped. The pain is bad enough to where I literally cant focus on anything else.
Is this normal?? What can I do to make it stop? Should I get some medication for this?