Achievements locked: help me

[bugmenot]

My brother, foolishly activated the cheats when I let him (kindly I might add) have a good on my machine. Now obviously with cheats activated you can't get the achievements. I reset the level and did it again, but still no achievements. I am completely screwed now? The achievements fully locked. I have reset the console, loaded and re done the mission, but still locked.. Is there anyway to get them a flowing again?

*runs off to beat on brother*:uzi::uzi: