feeling guilty

I'm 37 weeks and still holding on at work, I'm trying to work as much as I can before baby comes so my husband won't have too much on his plate when I'll be on maternity leave. But man I can feel this pregnancy taking a toll on me. I called off work today from a 6 hour shift and I feel so guilty. I've been feeling tired and feet on fire. And this is the first time I've called in since working there a year. But I think it's time to go on leave now 😞