to work or not to work...

Got an internal battle going on in my head today... was (sorta) offered a work from home position by my employer (currently only employed as a "temp" or "fill in" through a local health system of hospitals, in the recruitment/HR dept). I have worked from home on assignments for them, most of which include making references calls on applicants. Usually I just work during my son's naptime, so maybe about 10 or 12 hours/week for a week or two (perfect!). Well, they have a position open in which they might consider allowing me to work from home to do this on a permanent part time basis. The catch is that they would need me a solid 20 hours/week. My son doesn't sleep 20 hours/week in naptimes ;) Therefore, I'd need to enlist a sitter. So then enters the whole argument to why I'm a SAHM: to keep our kiddos with me vs. a babysitter/daycare. It's just a choice that we have made as a family, desiring to sacrifice in other areas to accomplish this. Well, we are at a very tight point right now. Hubby is working his tail off, providing the necessities for our family (read: house over our heads & electric and water running, cars to drive, & food on table). The thing is, it's just really tight. Right now I'm trying to figure out how to make due with a $80/mo budget for groceries(& household) for our family. God has amazingly provided extras for us, in the form of odd jobs (like my random work assignments once every 12 weeks or so) and gifts (i.e. four bags of groceries from "Mrs Anonymous" delivered to us) but we have been digging into (barely-there) savings most months just to cover it. I feel like one way God is using this time is to have us "get it" - to be able to figure out how to be strict budgeters - & to live within these slim means. If the time comes when we are more well-off, I want that learned strictness to stay in place so that we can give away the additional funds, to bless others with, as they have for us during this time.
Soooo... does that mean I work to actually give ourselves grocery money? (or tackle medical debt which is still hanging over our heads). Is this a no-brainer? But when do I take my son to a babysitter? He won't sleep outside the house so naptime will have to be rearranged or messed up. I don't want the only time I "see" him to be when he comes home after the babysitters to nap! The ideal would be to arrange a sitter that would take him after he naps here (I could work partially during his nap, then finish while he's at a sitter's). I'm not sure how long his nap schedule will stay this way, though. Most days he goes down later and has only been given me one nap/early afternoon vs. late morning & late afternoon naps.
LOL (shaking my head because I am such a nut to go back and forth and all around with this). I am typing this out to reassure someone (hopefully at least one of you SAHMs/WAHMs can identity) because my hubby and I are really trying to figure out what would be the best for our family. If I "had" to work, I couldn't ask for anything better (well, maybe except for a 12 hr/week position).

Ok, feedback time. Please tell me what I cannot see. Is this a no-brainer? Or, is it an excuse (at the expense of my child's "well being" and at the risk of forfeiting our decision for me to be at home with the kiddos) to forgo the strict budgeting?

(although it involves my son, this is just really something I'm struggling with as a woman who has decided to make motherhood her career right now...
I hope this counts as no mom talk, sorta ;)