Hi Pookie,
IMO your health will be at risk if you continue to work like this in the long term (unless you are like Bill Cullen!). Having said that, any time that I find myself in situations like that, and there have been one or two, I always look back at them and realise that I gained so much experience at that time. So, is there anything you are learning now that can improve your offering to the next employer? If so, it might be worth sticking around until you can get this experience. f not, then perhaps it's time to either have a chat with your employer or find something more suitable elsewhere.
Firefly.