/u/LucGap You've unfortunately may have rendered this personal statement unusable by posting it on the internet. UCAS runs a plagiarism check against all personal statements submitted, which would definitely include things posted publicly on reddit.
Firstly, remove this immediately - edit the contents to blank and then delete it. Secondly, in a day or two, google an exact extract (using " " to search for the exact extract). If something comes up, it's over - you must start again. If nothing comes up, there is a chance that you may have avoided indexing. However, it is still a risk and given that this has, at the time of writing, been up for 7 hours, I would strongly recommend scrapping it and starting anew.
I'm sorry.