Recently I've been sleeping between 10 and 15hrs a night and its really disruptive to my life before that I used to have between 4and 8hrs maximum.?

Many causes. See your primary care doctor: there are many causes for increased sleep including medical illness, medication side effects, the misuse of drugs and alcohol, sleep disorders and depression, bipolar disorder or anxiety disorders. If you believe you have symptoms of anxiety and/or depression, in addition to seeing your primary care doctor, you might consider getting a mental health evaluation.