Panic Attacks and University

I have suffered from mild anxiety for a while, but for around the past two and a half months it has become very extreme and has led to me suffering from panic attacks nearly daily. I think it was sparked when I found out that my mum had been suspended from work, which made us all as a family very stressed, particularly regarding finances and being able to pay my rent here. My anxiety has caused me to leave lectures, I am unable to stay in the library or concentrate on work without having a panic attack and I have stayed up all night crying over a fear of going into uni and going to tutorials. I did not speak to anyone at university about it due to embarrassment and fear of not being taken seriously - my university has a bit of a rep for being not the best regarding students mental health. I did, however, begin counselling quite quickly in the hopes that it would help ease my panic attacks and anxiety. I thought I would be able to get by without notifying uni, but I have failed essays and done much worse in my courses than I ever have before, despite counselling. This, of course, has only helped in worsening my anxiety and I know feel extremely worried and upset as I need to pass this year in order to get on to honours and I still have exams to do. I visited my doctor while at home this week and he has given me medication and confirmed that I am ill. However, I am really worried about telling my university about what has been going on and applying for special circumstances - which I think I will need to pass - out of fear that they will not believe me, and/or accuse me of only coming forward now in order to cover my back. Does anyone have any advice or similar stories? Is there any point in me doing so or should I just resign myself to failure?