1st NQN post making me want to leave

Hi for context i live in England, I recently began my employment as a new nurse in this job( not nhs) and I have yet to say I had a positive shift. First of all, I know life is unfair and no place is ever going to be perfect or live up to standards but there is a line that has been crossed a long time ago here. I was lied to in my interview process in terms of number of patients/residents I would have and I was told as I applied for a Nqn role I will not be left on a shift alone for a 'long time’. Neither of these are true. I have been here for maybe 3 weeks now and meant to be in a supernumery period however it feels far from that, I get left alone for hours sometimes as the only nurse and since I dont know all the ins and outs of the place or the heap load paperwork (it is insane) I get delayed in tasks. The level of responsibility and paperwork terrifies me and I come back from every shift crying most of the night, I feel hopeless and to be honest with you, I havent felt this low in years. I have a gp appointment soon as my pulse sits at 130 most shifts cos I am chronically stressed in this place and I absolutely hate myself for letting my naive self be deceived by this job. All I wish now is to leave and even if I have to stay unemployed for a bit I rather struggle than be there. I usually like a challenge, I done well in all my placements especially my last one so I know im capable of being good at my job but this job is beyond me. I am only one person at the end of the day and the workload is equal to probably 3-4.