Ripped Toenail Off

I banged my big toenail into the step when walking up the stairs and it came almost all the way off!
I went to the hospital and the doctor froze it and removed the toenail completely.
Now that the freezing has worn off, it stings continuously, as a fingernail does when it’s cut to the quick.
Is there any topical cream or something I can put on it to numb it?
Also, how long should I keep the bandage on before I dress it again?
Thanks for any suggestions