I know how you feel. I've been a single mom of one child (she's a teen now) when I was really young (20) and I can't imagine what it would be like with more than one. Anxiety provoking for sure.
You should check with your doctor about your meds, and it seems to me lately, you have to be really assertive with them. That particular med or med combination may not be working right for you. I've tried pretty much all the anti-depressants and none of them helped me one bit, even at the highest dose, just gave me side effects sometimes. Welbutrin was good for me because the side affect was that I wasn't very hungry often so I lost some weight on it, but it also kept me up all night and made my anxiety worse.
Now I'm totally off anti-depressants and am just taking anti-anxiety meds (see med thread).