Should I pursue this? Legal advice needed.?

[HarleyQuine]

I have been studying for four years in total. The first three years I was working for a diploma in English which involved 6 subjects, I did all 6 subjects and passed them all gaining the 6 credits I needed for the diploma. To get the final diploma the school had to request it and I had to pay for it during my final exam session. I paid for it.

Then I received my exam results for my final exam saying I had passed, but no final diploma. So I hassled the school on at least 6 different occassions and the headmaster said he'd 'sort it out'. Eventually I wrote an email to the education people myself and they said that I wasn't entered to receive my final paper and now the deadline has passed meaning I won't get my final diploma. So due to the school messing up twice I have wasted 3 years, and have a student loan of £2500 which I have to pay back not to mention the money I paid out for exams etc, oh and living on a very tight budget. Does anyone have any advice?