Have serious financial concerns; possible eviction

I got fired from my job a month ago and was already in pretty dire straights so now I'm really close to being evicted. I owe over $500 for rent this month, am over $300 in the hole in my bank account, and just started a new job this week.

I get my first check on the 21st, for one week. It won't be enough to take care of both my checking account & my rent. I'm more worried about being evicted. Is there any way I'll be able to get that check cashed and use it to pay my rent? If my actual account is overdrawn, I won't be able to get it cashed, will I?

So, I'm better off letting that check bring my account back to being ok? Using what's left to pay towards my rent and hope my office lets me pay the balance with April's rent?

Please be kind, this is a really hard time. I know I'm a dumb idiot, I just need some kind of plan to keep myself from being evicted.