Sick leave to maternity leave - Canada

I am 35 weeks and 3 days. I have a pinched nerve, am not sleeping well and have a job where I stand all day. My commute to work is about 45 each way. I wake up at 4:30am take my dogs out, shower, get my husband to work for 6:00 am (we commute together to save money on gas), then I start at 6:30 or 7:00 depending on the day. I work a job where I have to stand all day, though they have been accommodating and helped me so that I can sit for a portion of it. I find myself feeling sore while sitting as well. Mostly because there have to be a lot of ups and downs. I finish around 3:00, often have an appointment to make it to and then have to drive home, take the dogs out, make dinner, make lunches for the next day, do dishes and finally usually get to sit down for about 7:00 or 8:00. Usually I'll sit for dinner for about 15 minutes. I'm finding it all very overwhelming since daily tasks like putting on boots is no longer a simple thing.
I have been offered by my doctor to start sick leave but, I feel guilty. I worry about money and that the reduced income will be difficult for us because we have to renew stickers for our vehicles, my husbands license and he owes 250.00 in taxes due all around the same time. I know I can probably make it work, but I'm sure it'd be a bit easier if I just kept working.
Anyone else feeling this way? Any suggestions? Should I just suck it up and suffer through it?