"Cant get an appointment"

I called the GP today due to my health as I have been struggling to sleep for couple of weeks now , I had 0 hrs sleep for the past 48 hours,

when I called the GP today at 8am to make an appointment I was told they cannot give me appointment and someone will call me back later on the day to book an appointment for me, I advise them am at work from 9am till 5:30 pm therefore I wont be available hence why am calling at 8am to try book appointment for anytime this week.

I called back on my lunch break and spoke to one of the receptionist and advise them am still waiting for a phone call, they then advise me they have tried calling me as they have spoke to the Doctor who advise me to go see a chemist, told them I have seen a chemist already and had lots of sleeping aids which does not work, how can I go see a chemist again? all I wanted was to see a doctor due to me scared about my health.

I have been sent home today from work as I almost fainted and don't know what to do now as I cannot even see my own GP.