To start with, the provided image states that the password you're trying to use has a word that's been blacklisted (ie, cannot be used) This most likely means that you contain a word like "Password" or "ABC" in your password that is very common. Try to use a better combination of characters that do not match common dictionary words.
From there, while we can't figure out why a username/password is not working, (as no one here works for Mojang), I would suggest you take a moment to consider if you logged into any websites or services recently using the same account as your MineCraft account. Some (but not all) of the cases we have about username/passwords not working tend to come back to people logging into an unofficial "minecraft" services that's stealing accounts in the background. It's easy to get your account back, but the time it takes to recover it usually means someone has a dummy account they can mess with for hours until the owner fixes the issue.
This is very unlikely, but not impossible nor as uncommon not to be mentioned. It's more likely that it's just an issue with the password being typed incorrectly too many times, but barring that problem and any issue with the logon servers having issues, this is the next possible problem.