Mat leave / pay cock up? What can I do?

[bippitybopityboo]

I was due to start my mat leave on 1st July after 2 weeks paid holidays
However was diagnosed with preeclampsia at 32 weeks and advised to finish work earlier.
I called my manager and asked if I would be able to take my 2 weeks holiday and then start my maternity leave early rather than going on sick which she very kindly agreed to ans that was that.
Today I have found that my pay has been totally cocked up and I'm only going to be paid my 2 weeks holiday as my mat leave has not yet gone through with the pay roll.
They also said it may not start till 1st July as I have not signed a new form with the changed dates on. I was never informed I needed to sign or fill in any new forms.
They've basically said not alot they can do will email payroll and see what they say. It's leaving me with nearly a month of no pay at all. I would have been better off taking sick leave

Is there nothing I can do how can they expect you to be able to cope without you're money coming in?

It's really annoying when stuff like this messes up. Last year my payroll messed up big time and I ended up being paid half my salary in June. They gave me a loan until the following month and then just deducted it from the following pay cheque so it balanced itself out. Could you ask for something similar maybe?

Have you got any savings to fall back on? Or worst case scenario, any family that could lend you until work rectifys the situation and pays you the remainder of what they owe you?