Not sure if you tried this or know about this, but many times the password boxes won't register the first letter you type. Make sure you're selecting the box, type a couple jibberish letters just to make sure its typing properly, erase, type your PW than try again.
If that doesn't work, try the same thing while omitting the first letter of your new password, its possible the same thing happened when resetting your password so its a letter shorter than you think it is.
However it would also be a good idea to send a ticket to support or see if you can get ahold of a Mod personally (I'd do both since support is slow and mods tend to be quicker but its best to cover all your bases) Best case scenario is your password was just borked cause of the boxes and you'll get in within the hour, worse case is you've gotta wait a few days for Support to fix the issue. Sometimes they are faster, others they are not.
Good luck with your account though, hope it gets fixed soon.