Take a look at your posts, type the same thing correctly ("sometime" instead of "sumtyme", "been" instead of "bin") and see how much time you actually save. 10 seconds? 15? Max 30? How much clearing your head and figuring things out can you do in half a minute? You say you want people to help you instead of whining about your spelling. But here's the thing - bad spelling makes your posts more difficult to understand, it will take readers more time to get to the point. Good punctuation and spelling are good for a reason - they make communication easier and more efficient. And frankly, if you want people to help you then you should at least have the decency to respect the time they take to read your posts and answer them and a very good way to show that respect would be to use correct grammar, spelling, and punctuation so as not to make them helping you more difficult.
And the point you made about scientists' bad spelling and grammar reeks of cluelessness. Scientists' whole work depends on punctuality - you can't get your grant proposals accepted if your writing is worse than that of an illiterate teenager on acid and they could never accurately finish their experiments and data collection if the records are poorly written.
As for your problem... Sheffield is out of the question for you this year. I'm sorry, but that's the way it is. Their requirement for both BSc and MSci courses is AAB and like you pointed out they're one of the best in the country for this field so they get more than enough qualified applicants and there's no reason for them to take people who underperform so significantly. Even if they made lower offers for their BSc courses it would still be something like 30+ credits at Distinction for you - something you are still far away from. You've missed your offer by a whopping 15 credits and that really is a surefire rejection. Someone suggested deferring your offer, but that won't work either because you'd still have to meet the conditions of the offer by August 31st this year. A deferred offer will not grant you an extra year to meet the conditions. At this point you've got two options - go to your insurance this year or take a gap year, retake your exams, and apply to Sheffield for 2012 entry.