Diagnosis?

Hi,

I'm a 21 year old girl, currently studying at university. For some time, I've thought that I may have autism, and my mum agrees that I've shown autistic tendencies since early childhood. Some of my friends also agree that I display behaviours associated with autism - and my best friend, who was diagnosed with Aspergers as a child, told me that I am exactly like him. However, I've never had a diagnosis, because as a child my mum apparently decided I was fine as I was and did not need any support. I was wondering if anyone here was in a similar situation and if people had found a diagnosis to be useful to them, or if it is simply a label which is a pain to acquire and not much use afterwards.

Thanks :)