Depression / anxiety after recent Aspergers diagnosis

I was diagnosed with ASD about 18 months ago at the age of 49! Recently I have started having panic attacks which appear to be getting worse and now I’m starting to feel quite down. Does anyone have any experience with antidepressants as this is something that my GP has said might be an option. Also are there any counselling organisations specifically for autistic adults? I live in Sheffield. I’d welcome your ideas and suggestions