No problem!
I wonder if you would feel able to broach the subject more seriously with your parents? If they think it's likely you have it anyway, and if you explain to them that you think you would benefit from a diagnosis, I'd hope they'd take you seriously and consider going back to your doctor. They clearly thought it was important enough to try and get you diagnosed when you were younger, after all!
Obviously you don't have to do anything about it if you don't want to, but since you're posting here, I'm guessing that not knowing whether or not you're autistic is bothering you. If so, there's nothing to be lost by trying to get assessed again. I don't know what stage you got to in the assessment process last time, and I don't suppose you remember, but things have moved on since 6/7 years ago when you were last "in the system", and the NHS are now supposed to make assessment pathways clear and explicit. I have been doing some research this evening, and it looks like your GP needs to refer you to the community paediatricians (there's a list of people on page 4 at this link http://www.alderhey.nhs.uk/wp-content/uploads/2013/04/2013-Directory-of-Secondary-Services.pdf). Hopefully your GP should know what they're doing, though! Their waiting list is only about 18 months at the moment, apparently. The assessment process varies from area to area, but when I was assessed at 14, it was a few meetings with a psychologist, plus some questionnaires that me, my family, and my school filled in.
To change the subject - Pink Floyd were one of my first musical loves, too! Them and Muse.