can I recover my password file on firefox?

Maybe, depending on how you wiped it. Look in your Recycle Bin first. Firefox saves passwords inside your profile folder across two files: logins.json and key4.db. You have to keep both together for them to work. If you have a profile backup, just drop both files back in. Using Firefox Sync? Log back in and they might pull right down. I accidentally wiped mine during a PC cleanup once and an old backup saved me. If the files are totally gone with no Sync or backup, you're out of luck. Definitely export a copy next time since it takes like ten seconds.